Have you Installed the patch (ubbthreads-7-7-1p1.zip) as mentioned in the Version Discussion and Changelog?
https://www.ubbcentral.com/forums/ubbthreads.php/topics/262141/7-7-1-changelog-discussionThis patch fixes:
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2/ correct the "input=url" issue when attempting to submit changes in the Member Editor if the member has a homepage stored in their profile.
Download ubbthreads-7-7-1p1.zip and replace (overwrite) the files in your 7.7.1 forums with the files from within this archive.
