[Evolution] Cannot empty my trash folder!

["E. Zonneveld" <zedsoft zonnet nl>]

Hi All,

I am rather new to both linux ans evolution mail so
be patient with me.
Most things are OK now in evolution mail but I do 
recieve much spam from one mail account and I use a
filter that delete" most of it. 
However this "deleted" mails showing up in the trash 
folder, here starts my problem.
When I go to file en select "empty trash" I get an error.

--------------------
"Error while expunging folder."
Error storing '~/.evolution/mail/local ( mbox)':
Summery and mismatch, even after a sync
--------------------------

I do not know how to find a "trash" (or any other)
folder where my emails are.
I need to solve this very soon because now I have
something like 10.000 mails in that folder!
Help please

Edmund