Whitelisting of file extentions in sharepoint folder

Copper Contributor


If I have shared a folder with multiple people in SharePoint and I expect only certain file types to be uploaded into my SharePoint's shared folder (e.g. docx,xlsx, ppt, txt) and block all other types of file extensions (e.g. 7zip,rar,exe, dll) so that I can reduce the risk of someone uploading a malicious or an encrypted file, or some kind of source code.

I don't want to go by the way of blocking or blacklisting file extensions as that would be too extensive an exercise than whitelisting.

Do we have such options in SharePoint that allow us to control the file extensions that can be uploaded?

Just want to narrow down the risk from a security perspective.




  • m
1 Reply

Hi @sam2024,

Unfortunately, there is no place to set up a file type whitelist in SharePoint Online. We can only specify those files that cannot be uploaded to SharePoint. Maybe you can add all the common file suffixes in windows to the Blocked File Types and remove doc and txt to meet your needs. If there are other types of files that are subsequently prohibited from being uploaded, you can add them to the Blocked File Types.

Here are some other options:

  1. Information Rights Management (IRM): SharePoint Online allows you to use Information Rights Management to restrict what users can do with documents, such as preventing them from downloading, printing, or copying text. While this doesn't precisely restrict file types, it can help protect the content of your documents.

  2. Customized Form and Workflow: You can create a custom form for uploading files to the SharePoint library. In the form, you can add a validation step to check the file extension before allowing the upload. If it's not one of the allowed extensions, the form can reject the file. This can be done using SharePoint Designer, PowerApps, or other development tools.

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Kindest regards,

Leon Pavesic