desktop manager doesn't recognize my 8110

i purchased a "reconditioned" 8110 pearl a couple of months ago off of ebay. it was originally an at&t phone, but was fully unlocked. i have been using it with t-mobile and it has been working just fine. yesterday my phone came up with the message "app error 523" (it still boots up and i can make phone calls (can't get to my contacts list though), and by going to the switch application menu option i can surf the web for a little while, but then the message 523 comes up again and it reboots). i did a bit of research on the message boards on crackberry and decided to backup my 8110 using desktop manager and to then wipe it and reinstall the operating system, but once i downloaded desktop manager and started it up it won't detect the port my 8110 is on and also won't allow me to check the "detect my hardware" box (it's grayed out). my computer does detect my blackberry and has installed the drivers for it. any suggestions would be appreciated.