In the GPG4Win package there is another client GPA. Does it work? There is also the command line utility gpg2.exe in C:\Program Files (x86)\GNU\GnuPG\ Both Kleo and GPA aren't truly GPG clients they are more like GUI frontends that send commands to GPG2.exe behind the scenes. I would see if you can get gpg2.exe working from the command line as part of your troubleshooting.
Note stored keys are accessible from all clients regardless on which one was used to import/create them.
I don't know a fix for that error but it may keep you operation in the meantime.
I've been using GPA asif its Kleo for alittle while now. And yeah, gpg2.exe works.
-----BEGIN PGP MESSAGE-----
Version: GnuPG v1.4.10 (GNU/Linux)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=hz9e
-----END PGP MESSAGE-----
-----BEGIN PGP MESSAGE-----
Version: GnuPG v2.0.17 (MingW32)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=Eq6y
-----END PGP MESSAGE-----