[TYPO3] ERROR: malformed or missing URL detected

[Gunnar Jonsson]

I am trying to update the tip-a-friend extension. But when I use the 
tip-a-friend page I get the following error:
ERROR: malformed or missing URL detected

I am using typo3 4.0 and tip-a-friend 1.2.3.

I have seen a lot of people with the same problem in the forums, but I have 
not seen any solution to the problem. I searched for the error message on 
Google and found 104.000 items. Many items were from tip-a-friend pages at 
typo3 websites, so it seems that I am not the only one having this problem.

Does anyone have found a solution to the problem ?

Regards,
Gunnar Jonsson