I downloaded the latest msi today .7150 and installed over the top (internal updating was not working)
I got a message window from the em client installer saying that it needed to close a Panda CAV service. I did not allow this and rebooted.
It is not a good idea for another program to try to close your AV
I just installed version 2.6.7225 and got the same kind of message from Avast, my AV program, which had to do with the same thing, I think.
Try this, it worked for me: In the Accounts group, click the SMTP tab, and select “don’t use secured connection” from the drop-down menu in Security Policy. The AV program will monitor your sends and secure them.