ClassSync Terms of Service

These ClassSync Terms of Service set out the conditions governing the use of the ClassSync application and related services provided by DONGSEO Information System.

Effective Date: October 26, 2026

Article 1. Purpose

These Terms of Service (“Terms”) govern the conditions under which DONGSEO Information System (“DONGSEO”) provides the ClassSync application and related services through Microsoft Store, Google Workspace Marketplace, and other supported distribution channels, and define the rights, obligations, and responsibilities of DONGSEO and users.

ClassSync is a Windows client application designed to help schools and educational institutions manage Microsoft 365 and Google Workspace user accounts and educational environments.

ClassSync includes:

  1. the ClassSync administrator functionality for school administrators; and
  2. ClassSyncTeacher, a cloud file-copying functionality for users.

The permissions and functionality applicable to these two components differ.

Article 2. Acceptance and Application of These Terms

  1. By installing, accessing, or using ClassSync, or by accepting these Terms where acceptance is presented, the user agrees to these Terms.
  2. A person using ClassSync on behalf of a school, educational institution, or other organization represents that the person has appropriate authority to configure and operate the relevant functionality and approve required permissions on behalf of that organization.
  3. If a user does not agree to these Terms, the user must discontinue use of ClassSync.
  4. Microsoft 365, Google Workspace, Google Classroom, Google Drive, Google Calendar, Microsoft Teams, Microsoft School Data Sync, OneDrive, SharePoint, Whalespace, and other third-party services may be separately governed by the terms and policies of their respective providers.
  5. These Terms do not replace the terms applicable to Microsoft, Google, or other third-party services.

Article 3. ClassSync Service

  1. ClassSync enables school administrators to configure and manage Microsoft 365 and Google Workspace user accounts and educational environments from the administrator’s local device.
  2. The ClassSync administrator functionality requires an initial sign-in with a Microsoft 365 Global Administrator account.
  3. Functions using Google Workspace APIs require additional Google Workspace Super Admin authentication while the Microsoft 365 administrator remains signed in.
  4. Depending on the school’s identity policy, a school may configure Microsoft 365 or Google Workspace as its identity provider, and ClassSync may support management of corresponding user accounts across both platforms.
  5. ClassSync itself does not act as an identity provider for Microsoft 365, Microsoft Entra ID, or Google Workspace.

Article 4. ClassSync Administrator Functionality

ClassSync may provide supported functionality for:

  1. school-information management;
  2. creating, editing, and locally managing teacher and student rosters;
  3. bulk roster entry and editing using CSV files;
  4. ID Matching against existing Microsoft 365 or Google Workspace accounts;
  5. ID Synchronization for supported creation or updating of Microsoft 365 and Google Workspace accounts;
  6. OneID and account-mapping management;
  7. user-account domain management;
  8. Google Workspace organizational-unit management;
  9. Microsoft 365 license management;
  10. Microsoft 365 display-language management;
  11. group and membership management;
  12. teacher course assignments and student enrollment rosters;
  13. creation of Microsoft School Data Sync CSV files;
  14. Microsoft Teams class-team synchronization and lifecycle management;
  15. Google Classroom class and roster synchronization and lifecycle management;
  16. academic-calendar and calendar management;
  17. building, classroom, and resource management;
  18. generation of local roster files for Whalespace upload;
  19. local database backup and restore; and
  20. administrator handover backup and restore.

Article 5. School Information and External Data

  1. ClassSync may retrieve school information from an external data source or allow the user to enter information directly, depending on the country and operating environment.
  2. In the Republic of Korea, ClassSync may use relevant information provided through the NEIS Education Information Open Portal, including school information, class information, academic calendars, and school-level timetables.
  3. In Japan, ClassSync may use school-related data provided through edu-data.jp.
  4. In other countries, users may enter school or educational-institution information directly.
  5. DONGSEO does not warrant the accuracy, completeness, currentness, or continued availability of data supplied by third-party data providers.
  6. Users should review external data and ClassSync-generated results before applying them to school operations where appropriate.

Article 6. Rosters and Local Data

  1. The primary storage location for teacher and student rosters managed through ClassSync is the local ClassSync database on the user’s device.
  2. DONGSEO servers are not used as the central storage location for those teacher and student rosters.
  3. CSV files may be used for initial entry, import, export, and bulk editing of roster information.
  4. School Data Sync CSV files and local roster files for Whalespace upload are generated on the user’s local device.
  5. Users are responsible for appropriately managing the storage, access controls, retention, and deletion of local databases, CSV files, SDS files, exported files, and backup files under their control.
  6. Signing out of, exiting, or uninstalling ClassSync does not necessarily delete separately stored local files.

Article 7. Accounts and Administrative Authority

  1. Users may use only Microsoft 365 and Google Workspace accounts and permissions that they are lawfully authorized to use.
  2. Functions requiring Microsoft 365 Global Administrator or Google Workspace Super Admin privileges must be used by an administrator holding the applicable authority.
  3. Users must not use another person’s account, authentication information, or administrative privileges without authorization.
  4. Users are responsible for appropriately safeguarding account information, passwords, authentication tokens, and administrator authentication mechanisms.
  5. When ClassSync administrative responsibility changes, the school or institution should appropriately manage transfer or removal of accounts, local data, backups, and external-service access according to its internal procedures.

Article 8. ID Matching, ID Synchronization, and OneID

  1. ID Matching compares roster entries without an assigned OneID against existing Microsoft 365 or Google Workspace user information in order to identify an existing account.
  2. If multiple users have the same name, ClassSync does not automatically determine a single account based solely on the matching name. The administrator must review the matching result.
  3. When initiated by an administrator, ID Synchronization may create or update Microsoft 365 or Google Workspace user accounts within the approved permissions.
  4. OneID Management is used to retrieve and manage existing Microsoft 365 or Google Workspace account information and supported account attributes such as account domains, organizational units, and licenses.
  5. The administrator should verify affected users and account information before initiating account creation, modification, or synchronization.

Article 9. Groups, Classes, and Enrollment Information

  1. ClassSync may use teacher and student rosters to create and manage supported Microsoft 365 or Google Workspace groups, including grade-level student groups, class-level student groups, all-students groups, and all-teachers groups.
  2. ClassSync may prepare course-assignment information using teacher, subject, class name, grade, class group, and instructional-hour information.
  3. Student rosters and course assignments may be used to prepare class-level or subject-level enrollment rosters.
  4. Users should review relevant information before creating or updating groups, classes, or enrollment information in external systems.

Article 10. School Data Sync

  1. ClassSync may use teacher rosters, student rosters, course assignments, and, where selected, enrollment rosters to generate SDS V2.1 CSV files for Microsoft School Data Sync on the user’s local device.
  2. Generating SDS CSV files in ClassSync and uploading them to Microsoft School Data Sync are separate operations.
  3. The school administrator is responsible for uploading the generated files to Microsoft School Data Sync and configuring the Microsoft service.
  4. To provision Microsoft Teams class teams, a school may select Microsoft School Data Sync or the ClassSync Teams synchronization functionality as appropriate to its operating model.

Article 11. Google Classroom and Microsoft Teams

  1. When an administrator initiates the applicable synchronization function, ClassSync may use class and enrollment information to create and manage Google Classroom classes or Microsoft Teams class teams.
  2. After a semester or other instructional period, an administrator may perform supported lifecycle-management operations such as archiving, reactivating, or deleting selected Google Classroom classes or Microsoft Teams class teams.
  3. Administrators should review the applicable target and expected results before performing operations that affect data in external services.
  4. Signing out of or uninstalling ClassSync does not by itself delete classes or other information already created in Microsoft 365 or Google Workspace.

Article 12. Academic Calendars, Calendars, and School Resources

  1. ClassSync may use academic-calendar and timetable information to create and manage supported Microsoft 365 or Google Calendar events.
  2. Where an administrator initiates distribution of academic-calendar information to selected users, the applicable information may be created in those users’ calendars.
  3. ClassSync may use relevant school, class, timetable, and classroom information to create and manage supported building, classroom, and resource information.
  4. Users should review relevant destination information before creating calendar events or resources in an external service.

Article 13. ClassSyncTeacher

  1. ClassSyncTeacher allows a user to connect an existing-school Microsoft 365 or Google Workspace account as a source account and a new-school Microsoft 365 account as a destination account to copy user-selected cloud files.
  2. Supported source locations may include Google Drive, OneDrive, and, where applicable administrator consent has been granted, accessible Microsoft Teams or SharePoint-based files.
  3. When file copying is initiated, the selected source file is downloaded through a local temporary folder and uploaded to the Microsoft 365 OneDrive destination designated by the user.
  4. ClassSyncTeacher does not provide a user-facing function for deleting source or destination cloud files.
  5. If a file with the same name already exists in the same destination folder, the destination file may be overwritten by the selected source file.
  6. Users should verify the source and destination before initiating a file-copying operation.
  7. Users may use ClassSyncTeacher only for files that they are authorized to access and copy.

Article 14. Backup and Administrator Handover

  1. ClassSync provides backup and restore functionality for the local ClassSync database.
  2. ClassSync backup files are protected with encryption.
  3. When administrative responsibility changes, an administrator handover backup may be created for a designated Microsoft 365 account.
  4. A handover backup is intended to be restored while signed in to ClassSync using the designated account, and restoration with another account may not complete successfully.
  5. Users should securely store backup files and delete copies that are no longer required.

Article 15. Privacy

  1. The processing of personal information through ClassSync is governed by the separately published ClassSync Privacy Policy.
  2. The Privacy Policy describes, among other matters, processing purposes, categories of personal information, local storage, authentication information, transfers to external services, retention and deletion, Microsoft Azure usage, and data-subject rights relating to the ClassSync administrator functionality and ClassSyncTeacher.
  3. These Terms and the Privacy Policy serve different purposes. Where separate consent is required for particular processing under applicable law, DONGSEO will implement the required consent procedure.

Article 16. Microsoft and Google APIs

  1. ClassSync may use Microsoft 365 APIs and Google Workspace APIs to provide supported functionality.
  2. The availability of particular functions may depend on account permissions, administrator consent, organizational policies, API availability, and configuration of the applicable external service.
  3. Users may revoke Microsoft 365 or Google Workspace access granted to ClassSync through the applicable service’s security or administrative settings.
  4. Use of Google user data obtained through Google Workspace APIs is subject to the Google API Services User Data Policy and applicable Limited Use Requirements. Google Workspace Marketplace program policies separately impose user-data privacy requirements on Marketplace apps.

Article 17. Third-Party Services

  1. Microsoft 365, Microsoft Teams, Microsoft Entra ID, OneDrive, SharePoint, Microsoft School Data Sync, Google Workspace, Google Drive, Google Classroom, Google Calendar, Whalespace, the NEIS Education Information Open Portal, edu-data.jp, and other third-party services are operated by their respective providers.
  2. Use of a third-party service may be separately subject to the applicable provider’s terms, privacy policies, administrative policies, and other requirements.
  3. Integration between ClassSync and a third-party service does not, by itself, create or imply any sponsorship, endorsement, agency, joint venture, or partnership between DONGSEO and that third party.
  4. ClassSync is provided by DONGSEO even when it is distributed through Google Workspace Marketplace or Microsoft Store, and these Terms govern the use of ClassSync.

Article 18. User Responsibilities and Prohibited Conduct

Users must:

  1. comply with applicable law;
  2. comply with their school or educational institution’s security and privacy policies;
  3. process only accounts and information over which they have lawful administrative authority;
  4. not use another person’s account or authentication credentials without authorization;
  5. not access another person’s personal information, files, or accounts without authorization;
  6. not distribute malicious code, circumvent security measures, or interfere with normal service operation;
  7. not attempt unauthorized access to ClassSync or external services;
  8. not use ClassSync for unlawful purposes or to infringe another person’s rights;
  9. respect DONGSEO’s and third parties’ copyrights, trademarks, trade secrets, and other intellectual-property rights; and
  10. review applicable targets before performing operations such as synchronization, deletion, overwriting, or license removal that can affect external accounts or data.

Article 19. Software License

  1. Subject to these Terms, DONGSEO grants users a limited, non-exclusive right to use ClassSync for its intended purposes.
  2. Ownership and intellectual-property rights in ClassSync and related software remain with DONGSEO or the applicable rights holder unless expressly transferred.
  3. Except where expressly permitted by applicable law, users must not engage in unauthorized copying, redistribution, or resale of ClassSync; circumvent technical security measures; distribute unauthorized modified or derivative versions; or represent ClassSync or its marks as their own or a third party’s product.
  4. Nothing in this Article limits rights that cannot lawfully be restricted.

Article 20. Free Functionality and Technical Support

  1. The core functionality of ClassSync is provided free of charge.
  2. Users who complete school-domain usage registration receive technical support within the scope determined by DONGSEO free of charge for one year from the initial registration date.
  3. Updating registration information does not automatically extend the complimentary technical-support period.
  4. Installation, configuration, training, data migration, remote support, operational consulting, and other separate support may be offered as paid services.
  5. Where paid services are provided, the applicable scope, fees, payment terms, and other conditions are governed by a separate quotation, order, contract, or transaction terms.
  6. Listing ClassSync on Google Workspace Marketplace or Microsoft Store does not itself constitute an agreement with Microsoft or Google for DONGSEO’s paid technical-support services.

Article 21. Changes to the Service and Software

  1. DONGSEO may change or update ClassSync for security, compliance, changes to Microsoft or Google APIs, changes to external services, feature improvements, bug fixes, or operational requirements.
  2. Some functionality may change or cease to be available as a result of changes to Microsoft 365, Google Workspace, or other external APIs or permission policies.
  3. Where a material change affects personal-information processing, DONGSEO will revise the Privacy Policy as required by applicable law.
  4. Material changes to these Terms will be handled in accordance with Article 27.

Article 22. Restrictions on Use

DONGSEO may, to the extent permitted by applicable law, restrict access to DONGSEO-managed services or support where:

  • the user materially violates these Terms or applicable law;
  • another person’s account or authority is used without authorization;
  • conduct threatens service security or normal operation;
  • school-domain registration or technical support is obtained through fraudulent or improper means; or
  • the user materially infringes the rights of DONGSEO or a third party.

Access to a school’s Microsoft 365 or Google Workspace tenant itself is governed by the school or institution and the policies of Microsoft or Google, rather than by DONGSEO.

Article 23. Termination of Use

  1. A user may discontinue use of ClassSync or uninstall the application at any time.
  2. Uninstalling ClassSync does not necessarily delete separately stored local databases, CSV files, SDS files, exported files, or backup files.
  3. Accounts, groups, organizational units, classes, teams, calendar information, and other data already created in Microsoft 365 or Google Workspace are not automatically deleted merely because ClassSync is removed or the user signs out.
  4. Upon termination of use, users or their schools or institutions should review and manage local data, external-service data, OAuth permissions, Windows account connections, and backup files as appropriate.
  5. Requests to delete school-domain registration information directly held by DONGSEO may be made in accordance with the ClassSync Privacy Policy.

Article 24. Intellectual Property

  1. Copyrights, trademarks, and other intellectual-property rights relating to ClassSync, the ClassSync name, software, user interface, documentation, logos, and content created by DONGSEO remain with DONGSEO or the applicable rights holder.
  2. Microsoft, Google, and other third-party names and marks referenced by ClassSync to identify compatible or integrated services remain the property of their respective owners.
  3. These Terms do not grant users ownership of any third-party trademark.

Article 25. Service Availability and Responsibility

  1. DONGSEO takes reasonable measures appropriate to the stable and secure provision of ClassSync.
  2. Functionality may be affected by circumstances outside DONGSEO’s control, including Microsoft 365 or Google Workspace outages, external API changes or discontinuation, school or institutional tenant configuration and security policies, the user’s accounts, device, or network environment, and changes or interruptions affecting external data providers such as the NEIS Education Information Open Portal or edu-data.jp.
  3. Where an administrator performs an operation that affects an external system, such as account creation or modification, file overwriting, group or organizational-unit modification, license removal, or deletion of a class, the administrator is responsible for verifying the target and the intended result of the operation.
  4. Nothing in these Terms excludes or limits liability that cannot be excluded or limited under applicable law.

Article 26. Governing Law and Dispute Resolution

  1. These Terms are governed by and interpreted in accordance with the laws of the Republic of Korea.
  2. DONGSEO and the user will endeavor to resolve disputes relating to these Terms or ClassSync through good-faith consultation.
  3. Disputes that cannot be resolved through consultation will be resolved by a court having jurisdiction under the applicable laws of the Republic of Korea.
  4. Nothing in this Article excludes any mandatory rights available to a consumer or user under other applicable law.

Article 27. Changes to These Terms

  1. DONGSEO may revise these Terms due to changes in applicable law, ClassSync functionality, external APIs, Microsoft Store or Google Workspace Marketplace policies, or service operations.
  2. Where a change materially affects users’ rights or obligations, DONGSEO will provide notice of the changes and their effective date as required by applicable law.
  3. Where applicable law requires separate consent to a change, DONGSEO will implement the required consent procedure.
  4. A user who does not agree to revised Terms may discontinue use of ClassSync.

Article 28. Contact Information

DONGSEO Information System
Address: 421, 41 Nonhyeon-ro 87-gil, Gangnam-gu, Seoul 06235, Republic of Korea
Telephone: +82-2-564-7893
Fax: +82-2-564-7892
Email: classsync@dongseo.com
Representative: HONGJOO SHIN

Contact DONGSEO