After the upgrade K2 to version 2.6.3 is not working registration form K2. Issued 404 - Component not found.
After removal of the K2 does not work and the native form of Joomla (the same error).

Reinstall the K2 2.5.7. It worked.

Joomla 2.5.8.
Template "OT Corp MX"

Where to look for the problem? Does not affect whether the folder com_k2 in the site template?