"SE w810i - Too many messages, delete some from any folder"

This message started popping up every few seconds on my phone yesterday. If I click Yes to delete messages, it takes me to the mailboxes which shows 0 messages. I never even use text messaging. This is a Rogers phone in Canada.

I tried both reset and master reset and this problem would not go away. Couldn't find much information online, so I thought I'd post this in case it helps someone out in the future. I decided a firmware flash was the only way to fix this problem. I've never de-branded a phone before, so I was a complete newbie. I just started searching for info online and everything worked out in the end. Summary of the steps I took:

Files downloaded:
1) XS++ v3.1
2) USB driver (ggsemc.inf, ggsemc.sys)
3) FS: W810_R4EK001_FS_AMERICA_2_RED49.fbn
4) Main: W810_R4EK001_MAIN_GENERIC_HN_RED49.mbn

Backup GDFS:

*Removed memory stick and SIM card, battery charged to 100%

1) Turn off power to phone. While holding C key, connect USB cable.
2) Point Windows to location of USB drivers and install
3) Open XS++ program; it should recognize your phone and tell you a bunch of information about it. Make sure EROM CID and Color matches the firmware (49/Red).
4) Click the GDFS tab and click Backup GDFS. Disconnect phone when successful. ** Phone will not power on at this point (scared the crap out of me for a minute). Remove battery/re-insert and it will be fine.

Flash firmware:

5) Connect while holding C key again. Click on Flash tab and select the Flash Main firmware file, Flash File System, and check Customize File System. Phone model preselected as w810, and I chose AMERICA2 as CDA and Region from the dropdown list.

6) Hit the Flash button, twiddled my thumbs nervously for about 3 minutes. When finished, disconnect, remove battery and reboot.

Success! Problem solved, debranded from Rogers, and I can now use mp3s as ringtones. Yippee. Credit to the variety of guides people have written on the internet.