Getting this error on ALL ClickOnce application launches for a certain user. This started happening after a version upgrade (but happens to no one else).
I\'ve trie
The problem mysteriously disappeared after repeatedly deleting that folder, and attempting to reinstall. Perhaps there was a reboot thrown in there too.
Deleted everything in %user%\AppData\Local\Apps\2.0\
and it worked.
I realize this is an old question but I stumbled upon the same problem and found a different solution: The cause was an "&" in the ClickOnce network install path. Microsoft has confirmed this issue and stated they will not fix it: Microsoft Bug Report