You see duplicated files in the sync folder with the word "conflict" and a timestamp added to the file name.

If multiple computers make changes to the same file, file conflicts may occur. When this happens, Synology Drive automatically renames a conflict file to prevent data loss.

This article explains how Synology Drive handles file conflicts and how you can resolve file conflicts.

How Synology Drive names conflict files

A conflict file is typically in this format:

<original_file_name>_<client_name>_<conflict_time>_<conflict_reason>_<conflict_number>.<original_extension>

An example of a conflict file is: a_Andy-PC_Jan-03-0901-2013_CaseConflict_1.txt

• original_file_name: This is the file name part of the original file. For example, "a" is the file name part of the file "a.txt".
• client_name: This is the name used to distinguish Synology Drive clients when establishing connections. The name is different for each client.
• conflict_time: This is the time the conflict occurs and is in this format: <month>-<day>-<hour><minute>-<year>. For example, 9:01 AM January 3, 2013 will be converted into Jan-03-0901-2013.
• conflict_reason: This is the reason of the file conflict event. Currently, we have four known reasons for file conflict:
  • WhiteSpaceConflict: There is an extra space after a file name. For example, file "test.txt " or folder "test ".
    Solution: Simply remove the extra space.
  • TailCharacterConflict: There is a period after the file name. For example, file "test.".
    Solution: Simply remove the period.
  • CaseConflict: This occurs when you upload and sync two files of the same name. For example, files "test.txt" and "Test.txt" are considered the same under both Windows and macOS, even though the latter is capitalized.
    Solution: Use different names from existing files/folders.
  • TypeConflict: This occurs when multiple files share the same name, but differ in their file types.
    Solution: Use different names from existing files/folders.
• conflict_number: This is a number appended to the file name when another conflict file with the same name already exists.
• original_extension: This is the extension part of the original file. For example, "txt" is the extension part of the file "a.txt".

Possible causes of file conflicts and corresponding solutions

1. Cause: Frequently editing files in the synced folder before Synology Drive server and client have completed an initial indexing of the folder.
   Solution: Put off editing files until Synology Drive has finished indexing the synced folder.¹
2. Cause: When multiple users are editing the same file simultaneously, especially if the editing was done directly on the server. For example, one user is editing the synced files/folders on the server via SMB while other users are editing the same files/folders via Synology Drive Client desktop applications.
   Solution: If a synced file is to be edited by multiple users, please only do so from the same connection method (e.g., only via desktop applications or only on the server via SMB).
3. Cause: Uploading files with the same name but different file types to the synced folder.
   Solution: Before uploading files, make sure no other files (of any file type) with the same name exists in the sync folder.
4. Cause: The sync task may be interrupted by an antivirus program during the syncing.
   Solution: To prevent antivirus programs from interfering with syncing, add Synology Drive Client and the sync folder to the antivirus program's whitelist.
5. Cause: Multiple users are editing a file that only allows a single user to access, such as Microsoft Office documents.
   Solution: Use Synology Office for sharing and editing documents among multiple users. Refer to this article for details.
6. Cause: Syncing unsuitable files/folders, which are files/folders that are frequently modified or can be locked by other applications (e.g., log files, databases, or folders used for backup purposes).
   Solution: Make sure unsuitable files are skipped by configuring sync profiles for DSM accounts² or editing the Sync Rule of your Synology Drive Client sync tasks^{3 4}.
7. Cause: You are using other syncing programs⁵ to sync with the folder Synology Drive is syncing to.
   Solution: Use different folders for different syncing programs.