Plugin filename error

Hello,

I had trouble with the automatic update to 2.6.1 and in the end just uploaded the files to the server by hand. The tracking works again but now I have the following error message when I go to piwik settings:

“The plugin filename ‘EX0C0B~1/EX0C0B~1.php’ is not a valid filename”

And I can’t get into my settings anymore. Does anybody have a clue what it is? And more importantly how to fix it?

Thank you!

Boris