From the boot-up menu (press F8 when Windows begins to load...Same way to get in to safe mode.) select "Command Prompt Only" probably option 6.
From there:
--Put a disk in the drive
--type "A:" (no quotes)
--if you see "A:\>" for a prompt then type "dir" (without quotes).
--Observe the results. If there's directory listing, then your drive works properly. If not, then obviously the drive doesn't work right.
If your drive works properly
--------------------------
1) Boot into Windows.
2) From the device manager (System icon in Control Panel) remove the "Standard Floppy Disk Controller" under "Floppy Disk controllers" and reboot. You may want to power off before rebooting. (It sometimes works better that way.)
If your drive does not work properly
----------------------------------
1) Enter BIOS setup, (look for a prompt that says "Press key for setup")
2) depending on the system, under "standard bios setup" or something like that (it really differs) look for something referencing the floppy drive type.
3) If it's there, make sure it's settings are correct.
4) Exit the BIOS setup, saving changes if you intended to make changes. (If the settings were correct, do not save changes. It's possible to screw something up accidentally. Trust me ;-))
Oh yeah, did you put the cable back on exactly the same way? The red stripe should go to pin 1 on both the floppy and motherboard. If you need more help, just ask.