hi i try to install pidgin-ppa on knoppix hd install

but something gone wrong and now i get this error:

Removing pidgin-ppa ...
gpg: key "67265EB522BDD6B1C69E66ED7FB8BEE0A1F196A8" not found: eof
gpg: 67265EB522BDD6B1C69E66ED7FB8BEE0A1F196A8: delete key failed: eof
dpkg: error processing pidgin-ppa (--remove):
subprocess installed post-removal script returned error exit status 2
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)

and now i am unable to use package installer because of this error

what can i do to fix the error?

thanks best regards