Jayr,Unless Ard changed it, you have to have a minimum amour of posts in order to use the PM function. I believe it is 25. This was due to spamming by new members via PM.
Back about a month or so ago, we were having new members that had migrated from posting spam to sending it via PM's. This is why the policy started.Jayr,
That is probably my problem. When I go to the envelope as others have suggested, it doesn't give me the option to "start a conversation". I wasn't sure if I needed to turn it on somehow.