Applies to: Microsoft 365 Backup for OneDrive and SharePoint

Summary

In some OneDrive or SharePoint backups, certain files may be skipped because Microsoft Graph does not provide a file hash for them.

Our backup platform uses file hashes for verification and integrity checks. When Microsoft does not return the required hash metadata, the file may not be processed normally.

This is caused by Microsoft 365 / Microsoft Graph metadata availability and is not a backup platform failure.

Cause

Microsoft Graph only returns file hashes when they are available. For some files, the hash value is missing from Microsoft’s backend metadata, even though the API request succeeds and the file metadata is accessible.

This may commonly affect:

• Older or legacy files
• Files migrated into Microsoft 365 using third-party tools
• Files that have not been accessed or modified for several years
• Certain SharePoint system files, such as .aspx

Resolution

In many cases, Microsoft may generate the missing hash after the file is accessed or updated.

Ask the customer to try one of the following actions:

• Open or download the file
• Modify and save the file
• Re-upload the file, where feasible

After this, allow the next backup cycle to complete and verify whether the file is backed up successfully. As a safety mechanism, when a file is missing the required hash metadata, our backup platform skips only that specific file and continues with the remaining files. This prevents the entire backup operation from failing because of a single file with missing Microsoft metadata.

Important Note

There is currently no Microsoft-supported bulk API method to force hash generation for all affected files.

We continue to monitor Microsoft guidance and apply handling logic where technically possible.