I had this message as soon as put the installed the PR1.2 rc and have been banging my head against a wall since.

This fix relates to my rootfs NOT being full, it was only 55% full, and I had upgraded to PR1.2 rc. This solution worked for me, and admins feel free to copy/merge this post to the PR1.2 RC Helpdesk thread regarding the conversations app breaking if others find it works for them too.


Now to start, I used WinSCP and navigated to:-

/home/user/.rtcom-eventlogger/

Inside that folder I had the files:-
el.db
el.db-journal
el_archive.db
el-v1.db
el-v1.db-journal
backup.tgz

I copied all 6 to a local folder on my pc, and then deleted them from the N900. (Baring in mind my conversations app was broken already, as it didn't load any conversation at all)

I then loaded the conversation app in the hope it would automatically create a new .db file, (which it didn't) so I closed the conversations app, and restarted the N900.
Again on WinSCP, I navigated to /home/user/.rtcom-eventlogger/ and I copied all 6 files from my local folder on my pc, back to the N900, restarted the phone, and to my amazment when I loaded the conversations app, my texts and IM's reappeared!

I looked at the dates from the .db files on the N900 and noticed that el-v1* files had a more recent date change, so to save further space, I deleted the other 3 files from my N900 and kept the el-v1.db & el-v1.db-journal files.

Now to my horror, I got the awful message
Unable to receive or send new messages.
Device storage full.
Remove data to free memory.
Every 15-20 seconds, and it drove me mad!!! But, I came upon a solution.....Open X terminal and write the following:-

mkdir /home/user/.rtcom-eventlogger/BACKUP

mv /home/user/.rtcom-eventlogger/el* /home/user/.rtcom-eventlogger/BACKUP/


And that's it!
You may not have to reboot either. Just load your conversation app, and you should see new highlighted messages, if you do, problem solved but incase you havent got new messages, just wait 30 seconds or so, and if you see the yellow banner, try a reboot, if you don't see the warning message, all fixed

(A Further Note:- If you still see the warning message after all this, then its likely to be something else causing it. Again, this was a fix I found that worked for me. Hopefully the wonderful techies can see what the precise cause of this problem is by analysing this fix, and simplify the process, but this is what I achieved step by step. I hope it helps)