Knowledgebase

Answer / Solution

This error is caused by an operation that is part of the deduplication process and tries to consolidate the different permissions of the duplicates.

Hardlinks all share the same permission settings, so the deduplication process tries to ensure that access rights that a user previously had will still apply after a deduplication.

Here's an example:
Assuming you deduplicate two duplicates "file A" and "file B".
File A has "read only" access for user X
File B has "read and write" access for user X
File B will be replaced by a hardlink that points to File A
The "larger" set of access rights from File B has to be applied to File A as well

In summary: When one of the files is replaced with a hard link to the other, the process will try to merge the permissions of the underlying data. In the example above, the consolidated access rights would be “read and write” for user x. 

However, this operation is only successful, if the current user is allowed to change access rights for that particular file, or for files in the current folder. It is important to keep in mind that having the access right to change or write a file does not automatically include the access right to change the permission settings of that file.

If you receive an error message "Failed to merge permissions: Access is denied", then this means your current user is not allowed to change these permission settings and no deduplication will be performed for this set of duplicates. 

This can be the case either if he does not have a "Allow" entry for the operation "Change permissions", or if an explicit "Deny" entry exists for that. It is also important to note that a “Deny” entry will always overrule a "Allowed" entry, if both are set.