My device manager says this hard drive is working fine but when I try to expand or open the drive I get a message saying "the disk in drive e is not formatted" This is added 3.5 inch Maxtor 250GB with an ultra ATA serial card.

Right click "My Computer" >properties> hardware> device manager. Expand "disk drives". Right click your seagate drive and click uninstall. Reboot your computer; the drive should automatically be reinstalled.

have you tried
control panel admistrive tools,computer management,device manager scroll to disk drives + to expand if you can see scan disk drive right click you can trubleshoot or select properties select driver update driver,roll back driver or uninstall remembering to reinstall the driver
hope this helps

I do have the same problem with my tom tom920. I do have windows 7. When I plug it in message on my comp i get message USB device not recognized. Is there any solution?

Do you see the CDrom drive from the Device Manager? Right click on My Computer and click Manage. Click Device Manager and on the right panel, expand the DVD/CDROM drives. Check if your cdrom is on the list. If you can see it, try to right click that and Update the driver. You will need to have the installation disk for your cdrom.

If you dont have an installation disk, try to right click it and choose uninstall the drive. Next, you reboot the computer. The system should rediscover the drive.

If this does not work, please let me know.

This is usually a corrupt USB driver for the device. On the machine that has trouble recognizing the drive:
right click my computer
click on properties
click on device manager
find the USB devices, click the plus sign to expand the tree.
Plug in your drive, see which new device appears, if it has the exclamation point, then right click on the device and click uninstall. Reboot the system.

I found this on this site. in case you havent seen it. It worked for me. Try this:

When I disconnected my backup drive and plugged in a USB drive the other night, my Windows drive letters got all wonky. D: became G: became F: became H:, and a bunch of my shortcuts didn't work anymore.
But it's easy to reassign the drive letters of your choice to add-on disks in Windows. Microsoft says you should log on as an administrator, and from Administrative Tools in Control Panel:
Double-click Computer Management, and then click Disk Management in the left pane.
Right-click the drive, the partition, the logical drive, or the volume that you want to assign a drive letter to, and then click Change Drive Letter and Paths. Of course things can get wacky if the disk is in use - by your computer or another on the network - so proceed with caution, you drive alphabetizer, you.
How to change drive letter assignments in Windows XP [Microsoft TechNet] Read More: Windows, Hard Drives

Try connecting it to another computer. If you can see your data then back it up etc.
After you have recovered your data connect it to your computer, from Disk Manager, remove the partition, recreate it again and then format the drive, hopefully your external drive will be operational again.
There is a possibility that the hard disk has died and you will have lost your data. If you are desparate, hard drive data recovery companies charge an arm and a leg to recover data from dead drives.

Just because the device manager says the drive is working fine doesn't mean it is. If it won't recognize the ZIP disk, either the disk itself is bad or the zip drive is bad. I would try another zip disk and see if it will read a known good zip disk.

Hi
Please connect your hdd and go to disk management right click on my computer on the desktop g to manage and iskmanagement ..
check your hard disk is listed there or no if yes check it have drive letter if no please right click and add drive leter.if its there then check it has a format like it writng ntfs or fat32 if there then rigt click on the left hand side pan and say reactivate if still dosent work may be u need to format it. or use a third party software like hard disk regenerator or mac disk worior...
THANKSAND REGARDS