Whoa! Hold on a minute! OK. Probably longer then a minute.
But those tools are going to erase any data already written to that pen-drive (which is ok if the drive is empty but am guessing is probably not)
There are some other things to try before getting to that point
Plug the drive directly into the computer USB port (not through a USB hub. As you may have
=> A bad hub
=> Another device attached to the hub causing problems
=> Too many devices needing power plugged into a hub
Assign the drive a new drive letter. (is a problem if u assigned it a drive letter before but that letter currently being used by another device)
Click Start->Run, enter: diskmgmt.msc to start Windows Disk Management tool.
Does a new entry show up in the tool display when the pen drive is plugged in???
If yes, rt click the entry. select Change Drive Lettters and choose a letter among the choices Windows gives you
Use a disk partitoning tool to attempt to recover deleted partitions. (fyi.. don't ask what may have lead up to it... but this was the solution i tried one time when a friend's usb drive started having the "not recognized" problem)