QQ Mail 550 Ip frequency limited errors (and how to solve them!)

QQ are quite naughty in the way they give errors. They blatantly lie.

eg – the allegedly (but not true)

550 Ip frequency limited. http://service.mail.qq.com/cgi-bin/help?subtype=1&&id=20022&&no=1000725

If one visits their site and translates their description of the error, you get this:

qq.com has a restrictions on receive mails frequency. If SF side send too many emails to QQ mail box, then some emails would be bounced by QQ. The limit policy is as below.

*Number of Mails sent per minute limit reached: Block IP for couple minutes

*Number of Mails sent per hour limit reached: Block IP for couple hours

*Number of Mails sent per day limit reached: Block IP for entire day

Please refer to http://service.exmail.qq.com/cgi-bin/help?subtype=1&&no=1000725&id=20022  for the details of QQ policy. 

Would that it was true, its bogus unfortunately. I have a client that sends a total of 1 email to qq roughly every month. They still get that error.

Whats the actual issue?

The sender ip has been blacklisted. The ‘mail’ limit is effectively zero.

How does that happen?
The more report complaints about your mail from QQ clients, the more IP restrictions get set, because the number of new IP’s that can send to Tencent is very small, once complaints are received, the IP reputation may be reduced to zero. 

Whats the solution?

Have a client with a QQ address whitelist you as a sender using the following form.

http://en.mail.qq.com/cgi-bin/help_feedback_rcverr?sid=v0QuNKY9WU-3eQVQ,2,en_US&nocheckframe=true

Have them enter the sender email address in the top. (eg someuser@blockeddomain.com)

Optionally paste in the bounce message at the bottom.
Click the blue button.

It will then prompt you to whitelist the sender domains.
Once whitelisted, you should be able to send mail again (at least until more QQ users have blacklisted you!)