New support for # and % in SharePoint Online and OneDrive for Business


In the upcoming weeks, we’ll be shipping support for # and % as supported characters in file and folder names across document libraries in SharePoint Online and OneDrive for Business.  This will allow people to create, store, and sync files containing # and % characters whether those characters are used as a prefix or suffix to the file or folder name.  # and % will be limited to use in file names in addition to SharePoint Online and OneDrive for Business document libraries and related folders. 


More information here:



24 Replies

Our Office 365 admin - would like to know if there will be complications with future updates, if we run the powershell SpecialCharactersStateInFileFolderNames Allowed now?


No. You should be fine. This is not a hack, it's a fix.


Thanks for you reply Stephen. Are there any points where we should be carefull it we run the fix? What is the estimatet rollout date in calendar terms, think month?


@Stephen Rose, our use-case is completely the other way around.


We want to stop users from uploading documents with special characters. We are sick and tired of all kinds of weird filenames uploaded to our SharePoint libraries. Filenames that are a hundred miles long punctuated with all kinds of characters!


Is there a way to block all/selected special characters instead of allowing?


This has already been rolled out. You just need to follow the instructions in the post to activate on your tenant.