@computerinfo21
I think you'll find it more problematic when messages have a null group_uid than a missing remote_uid.. it's group_uid that lets the phone assign a message to a conversation...

e.g. if I text these numbers:
+447711223344
07711223344
00447711223344 (for most countries where 00 is the international escape code)

It goes to the same person but the remote_uid field is different in each case. As is standard with phones, they take the last 7 digits and assume it's unique to a contact, thus removing the problem that prefixes cause the same number to appear differently

Try it by calling your friend, but swap some number *not* in the last 7 digits, for another.. Phone will say youre calling ur friend, but the call wont connect

For SMS in el.db the group_uid is the last 7 digits of the phone number.. Its also used in groupcache and from what I've seen so far groupcache is the table that influences the appearance of the message list (error icons, unread msgs etc)

you should also take care to truly only implement fixes of the nature described here on rows where service_id = 3 (sms) because you may end up screwing up your calls and chat lists if you apply blanket changes to services 1 (calls) and 2 (chat)

Good thoughts on the subject cjard, seem like good things to keep in mind when editing the database. But that's why a couple good back ups beforehand are done in case of a mistake.
Keep that in mind when editing the database folks, have to be careful & be sure the changes you are making actually make sense.
However, with that said, I am not sure if those things have gone wrong for others, but for me only the things I mentioned were problems. Going back to the update of the groupcache on those fields I believe.
I looked through the database pretty good before making any changes, and the first SQL statement of each step is to help narrow down if that particular problem exists.

The group_uid was always assigned correctly in my case, and the only places I was having problems were the SMS messages, those having problems with other areas will definitely need to implement other fixes. Thanks for warning them.

I hope you all would come up with a sustainable solution! Repairing database worked great for me, but it lasted until the next time N900 got overwhelmed and screwed up to loose 11 sms in a row from a thread (both sent and received).

i still have the problem, unsent and error messages are gone, but still everytime i send a message and when i receive a message, it still did not update on my conversations. i still could not see the new sent and received messages. i don't want to loose my messages. please help me

The problem sometimes happened on my device when a miscall and an sms alert me at the same time. After that when i am going a send an sms, its just in a pending status. But the receiver already receive my sms. And after i rebooted my device, the conversation normalizes again.
But in this case, an sms and a miscall alert me at the same time. So i just tap the miscall notification to close. And prioritize to open the sms. After i deleted the sms, i saw the number in the miscall appeared in my conversation with an "arrow icon" which should not be in the conversation. I deleted that number in the conversation and when i open again the converstion, the number that miscall me keeps on coming back in the conversation. So i deleted the number in the phone log as well. Then the number didn't show on the conversation anymore. But when i am going to send an sms, it doesn't show any pending, nor any sent items. Even the sms should be on top of the conversation list. I rebooted my device a lot of times, but no success. The problem still exist.
I followed the instructions on the first page, and its true, the messages with the pending status fixed! But the problem of not showing the sent items or even the message should be on the top pf the list still exist. My conversation is not updating anymore. Even when i receive an sms, i could not open the latest sms that i received, i can only open a message thru notificatgion. But afetr the notification disappeared, there's no luck to open the message anymore.
I also tried to back up and restore the messages but the problem still exist.
Anyone could help me please. I don't want to delete my messages.

anyone could help?

Well maybe this will help.
I just kept repairing anything that messed up for a while, but got tired of it today. looked up some other options & I decided to do a 2 part back up solution.

First, I looked for & found a program to keep the messaging & call history on the phone: glogarchive.
It is slow for accessing the whole history of long conversations, but it has a search feature that is reasonably fast even on my almost 16000 events. And usually what I need is to find a specific message, not so much read an entire conversation, which is still possible, just slow.
Just archive messages & you have a good copy that is searchable.

Second, always wanting multiple backups, I went offline & renamed (moved) the database with the date to keep a copy from today just in case.
From the terminal:
Then I restarted the phone, all messages & history were gone from phone but safe in glogarchive to refer back to later. You could also probably just clear the big conversations & help some, but I wanted everything working like new, & so far it is.

Hope this helps some, or gives some ideas. I know I could archive messages in the Nokia Suite (which I do have a backup there too, can't ever be too safe ), but when I want a message from the past, I want it on the phone & usually am not near my computer.

Well, this issue has now spread to call log. The N900 doesn't record some incoming calls in the log so I can't see the call I had.

I am growing tired of fixing the database, and this is anything (perhaps the funky USB port) is going to force me to buy another phone. Too bad there aren't many other phones with video skype, great calendar, decent email interface, and hardware keyboard.

Any suggestions what to buy in place of N900 or what to do with loosing sms?

Thanks, and Happy New Year!

Worked for me. I had a contact that got stuck always showing my sent messages as pending, and the status updates properly now. I used sqlite3 on the phone to edit the db in-place instead of jacking around with copying files back and forth and screwing with permissions (I still made a backup beforehand, of course).

Is it possible to programmatically recover the remote_uid? I noticed that the messages that were missing remote_uid still showed up in the correct conversations.

Any update on the possibility of getting this into the CSSU?