Computer running extremely slow

I think the computer is infected with a trojan and may have some registry issues. I have am currently running avast again to try and resolve the issue in safe mode, but the speed is painfully slow.

follow instructions and attach Malwarebytes and OTL logs http://forum.avast.com/index.php?topic=53253.0

It says that there were no threats, but something is wrong.

and the important one … OTL diagnostic log …

Log experts are notified

It says that it can not find the specified path to save the otl text files.

what is it?