users get email notifications of PMs they cannot read or reply to

Users report that they get email notifications that they got a personal message,
but are unable to read or reply to such messages, as they haven't made the minimum number of posts to have that privilege.

It would seem the best solution would to be not to allow other users to send such messages to them in the first place, with an explanation that the person who you are trying to send to has not yet reached the level where they can use personal messages so there is no use sending etc.

http://www.bdsm.com.tw/forum/viewtopic.php?f=5&t=1232&p=7092#p7092 is the case involved (however one must login to read it, Chinese.) Note the admin had changed the limit from 3 to 20.