USB flashdrive doesn't show up in XP

I have a very "Strange" situation. I had my 465gb Verbatim USB flashdrive plugged into my XP Pro & forgot it was plugged in so I rebooted. In the process of it rebooting, the loosely connected connecting cable fell off disconnecting it.
Once it booted back up, I reconnected it but now it don't exist on the XP. Don't show up in my computer nor when I click the "safe to remove" icon yet I hesitantly plugged it in my W7 & it shows & everything is good.
Did I mess something up on my XP?

I've run scans (Avast,mbam & SAS) on it & they came up clean.

I tried another flashdrive in same slot(s) & it works fine. Am so confused.

Just to be clear, have you tried the USB drive cleanup tool yet? (all your external disks, flash drives should be disconnected when you do)

Sorry, I didn't see your post till now.
It took time to find this thread but yesterday, I absently minded put it in the XP to transfer some
videos. Thinking nothing of it. This morning, my XP froze for unrelated reasons & was forced to reboot. It was then it occured to me my Verbatim USB drive was plugged in still so I let it stay & it rebooted fine & now the problem seems to have been fixed.
Technology is strange, isn't it.
I'll bookmark this thread for future reference, thank you.