Intresting.....you say you deleted 285 yet it's still there? Arr you could be right but however it would normaly say "cannot delete" or "MBOX in CCR".
Get a pen and document the following while you are in programming:
As some peeps are trying to say....Go into F983, MAILBOX,PRESS 1,CHANGE,DIR,OK,(you will see GEN DELIVERY),NEXT and go into every mailbox listed in there and see what EXT every box points to....will take about 10 minutes to do with 30 mailboxes, this will only tell hopefully what mailbox is tying up 285.
Sounds like you have a 4 port Startalk Flash but anyway even though you pressed 1 after pressing MAILBOX to get to Info mailboxes I believe normal boxes still show in there too.
If you have gone through each box using this method and have gone through the CCR tree and checking the paths as Arr mentioned and still a problem then you have a bug in the software....some bugs with a particular mailbox can be cleaned by a reboot and sometimes not, in that case you have a big bug and in that case you would need to re configure the vamil from scratch and re program everything, to do so Press 1 after F983 and spell REINSTALL.
I suggest first to delete 285 again then reboot the vmail simply by unplugging the black power cord to it and wait 60 seconds then power it back up.
To test try to leave 285 a message and if it still says not initialized then try to initialize it (F981,OTHER, 2850000) then go back into programming and see if you can alter the settings and if still corrupt then do a REINSTALL.
You mentioned that you had some powerfails and I bet some of those were brownouts....Star Talk Flash units do not take brownouts as easy as all the other vmail models however still painfull.....Start Talk Flashes are know to fail completely and you have been lucky.
Also when you go into F983 can you press 9 once logged in and tell us the version # you see.....1.7 was pretty buggy if I recall.
Good Luck!
CC