I am trying to attach file which is about 1.8mb. It tries for a min or so and then it says can not find server. Forum is working fine though.
Where exactly is that option to change the upload file size limit?
Link to your forum and a test account?
Can you check your System Health (in Admin CP --> Tools / Maintenance). What is the value of "Max Upload / POST Size"?
PMed u the id and pass.
-----------------EDIT------------------
This is what it says:
Not Acceptable
An appropriate representation of the requested resource /editpost.php could not be found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
I am so sorry but I didnt really understand instructions in that link.