Problem

We need to restrict users from uploading files with specific extensions.

Solution

- First create a user class, if we want to apply the upload restriction to specific users. If we want to apply the upload restrictions to all SecureTransport users, this step is not required.
- Next, go to Access > Restrictions, go to the Upload tab, and click the "New Entry" button. There you can specify the path/filename (for example, "/*.exe") that you want to restrict, set the Allowed field to No, and set the user class to which this should apply (or * for all). Then save it using the disk icon to the right.

Note that if you use certain SSH clients (such as WinSCP), they may transfer files with an added extension (such as ".filepart") to allow for restarts. In that case, you may have to add two rules, one for the base extension (such as .exe) and one for the additional extension (such as .exe.filepart).