This happens with some users and until it is fixed here is a workaround:
When does this happen? When browsing submissions from the hardware library, example:
When you click "69" it links to link
It says "No submissions found." when there should be 69 submissions.
What you need to do is edit the url from "username=pilu[...]" to "user=pilu[...]" or, if you know your userId, "userId=99287[...]" (Easiest way to find your userId is to go to the "My Account" page or your forum profile page and look up the name of your signature image http://hwbot.org/signature/u99287.png)
Result:
With "user"
With "userId"
Now if when you click the arrow to go on the next page, the page becomes empty and/or you see other people's results, add "limit" parameter to the url:
Result with &limit=100:
With "user"
With "userId"