Roundcube won't send an email of anything more than a few lines long

[billywind]

I have been using Roundcube 1.2.5 on Windows/IIS, it was working fine for about a year then suddenly I am getting the following behaviour:

I can send a very short email eg 4/5 lines long.  If I go anything over that it just says "Sending Message", hangs and doesn't send the mail. In order to reply or forward I have to remove all previous content and keep my emails short.

Any help gratefully received.

[JohnDoh]

Have you made any changes to your setup recently? Are there any entries in the Roundcube error log or the browser console?

[rfanch3r]

I have the very same issue so looking forward to what the answer might be. Please look under Sending Issue.

In my case I have no error messages or logs, just sits there saying Sending Message forever.

[rfanch3r]

Anyone have any ideas on where to look?

[JohnDoh]

is there anything in your smtp server log? what if you enable smtp_debug in roundcube, anything in that log?

[rm13]

Could it be the php post size got changed incorrectly?

php_value   post_max_size 6M

Not really sure how Win/IIS works for where to check that.