Webmin Error - Missing Headers

Hello everyone,

I made an update Webmin theme during the time that had the system partition of the server 100% occupied and gives me the following error:

/session_login.cgi : Missing Headers

Also this one:

Temp file clearing is not done for the custom directory /home/tmp

You can see here: https://ns300398.ip-91-121-31.eu:10000/

A solution without reinstalling Webmin?

Nobody has an answer?