I have had handcent almost from the get-go, and have it set to not delete messages.
I had sms backup for gmail installed and was sure it was the culprit. my phone cleared out texts twice, and when I checked last backup it was between texts... hmmm.
so I turned it off.
lo and behold, a while goes by, and bam, they're all gone again, and now I don't have a back up. A month and a half of texts. gone. This is so frustrating. I don't have anything really important, but I shouldn't have to expect that my phone can't figure out how to manage a fairly simple database...
On a side note, I have my backup pro, but it sucks at running a weekly backup. The only backup is a manual backup I have from 2 months ago.
So as I understand it this problem happens to peoples phones who:
have a small limit
have a large limit
have no limit
have handcent
have no 3rd party text apps at all
and happens randomly, not when receiving a text?
Anyone have anything else to that list. I'm trying to sum up all of the issues in one place for clarity.