please help - continuous error messages popping up

I don’t really understand the problem that I have but I’ve been getting these two particular error messages from avast in the last few days, they would pop up every so minutes.

http://img13.echo.cx/img13/3964/avast7bi.jpg

Can you please help me in explain and stopping this error/time out… also following that when I press YES there is this error that pops up…

http://img13.echo.cx/img13/9356/avast20mu.jpg

and the email would change for the sender and receipent and I would press don’t send. I don’t really know what is going on… whether I have some sort of virus… it does not indicate what exactly I have… nor is it fixing it…

Please help, thank you.

It seems you got infected with a malware that is sending out mail messages. You should scan the whole disk and remove the infection.