(anti-spam-content-type' contains invalid characters, aborting request
 

Recently suddenly my website started returning the following errors:

(anti-spam-content-type' contains invalid characters, aborting request

I checked with each script and mod provider but all have said they dont sent this. This is causing forum to not allow attachment / image getting downloaded and return the internal error 500.

Can anybody point out what can be done?

I've never seen anything like that before, while you are waiting for somebody that may know about it, have you checked your attachment MIME type & Headers to make sure nothing is screwed up?

Example of one of mine below.

Attachment 155785

Oh! Thanks

This is what was an error. I corrected it.

Hello,

Thank you for your hent, It helped me fixing my issue displaying the forum attachments.