I won’t guarantee this applies to each and every similar situation and as you will notice, it might not work for some of you. The behavior is so strange that it took me a while to find a solution without doing something more radical.
What I’m trying to say is that even if it seems it also represent your issue, it might not fix your problem and the even worse part is that I can’t give you much details on what happens or even some logs to match facts as I couldn’t record any and it was more like a blind catch.
Let me present you my scenario. I’ve recorded an incident from a user that said he can’t see any of the usb flash drives (sticks) he tried. At least two tested and none displayed in windows explorer (my computer).
In order to avoid losing time and to make sure it is not a hardware problem (for example physically damaged storing devices or USB port) first I checked to see if the device is detected and if the operating system detects a change, a new plug and play device. For this, I consulted both Disk Management from start – run – “compmgmt.msc” without the quotes, hit enter – navigate to Disk Management. The drive was here, with an assigned letter. The file type which was FAT is also irrelevant for this case because it can also be a NTFS formatted drive. When you right click it and use open or explore option, you would get a message that the drive can’t be located or the path does not exist.
I also checked the “safely remove hardware” feature from the bottom right corner, that is displayed when you insert a plug and play storage device. This feature could also detect all the flash drives inserted but it wouldn’t render them visible in windows explorer.
I then decided to change the drive letter assigned, an old trick that would re-write some OS values and sometimes lets you access such drives that couldn’t be accessed before, due to whatever corrupted settings or faulty use (misuse) or bad installation. In other words, if sometimes you will find a drive missing or inaccessible in My computer and you can see it in disk management you can apply this workaround and it might work. You can consult this article to see what I’m talking about: http://compinfopro.com/change-drive-letter-assignments-windows-7-vista-windows-xp/
If the above failed and you still can’t access the drive, or even better if it is missing from your windows explorer, try the below solution but don’t forget to backup your registry entries before. Sometimes it can harm your computer and the only way to get it back is to get the old settings to registry settings via safe mode or restore. How to backup your registry entries? Open up registry editor by typing start – run – “regedit” without the quotes and hit enter. Select the tree you want to backup (usually the one you will modify, for example HKLM or HKCU) and then from upper menu select file – Export. Give it a name and store it somewhere on your hard disk drive.
SOLUTION to cannot detect USB flash drive or an external hard disk drive:
Open registry editor with Start – Run – type “regedit” without the quotes and hit enter. Registry editor will open up. You will have to locate two entries inside a subkey.
You should have in here, either both of them or at least one of the entries called:
Delete both of them if present (right click the red marked entries on the right side of the print screen and delete – confirm with yes). If one of them missing, even better, just delete the one present, in my case it was UpperFilters.
Next: REBOOT THE COMPUTER.
After computer restarts, depending of what software you have installed and what storage devices are still connected, it might give a few errors saying something that it fails to install some software. Those are just some unimportant automatic steps that should be completed (part of the recovery process) but most of the times fail AFTER it also fixes the error – the actions are happening in background. Don’t worry! Just let the computer do his schedule. It might look like you’re in trouble, for example a restart loop, but it won’t. Usually it reboots 2-3 times tops. Everything will be okay after this and you should be able to log in and open the disk drives you were trying to open when the problem started to show its ugly teeth. This will work weather it is an USB flash disk drive stick, a disk drive or a phone connected as a storage device as long as the above also apply (can be detected in disk management, can change the letter assigned, and so on), else it is not this case and the above solution won’t fix your problem.
I am willing to help you with any other scenario you might find, as long as you share it with me. Even if I may not fix your problem, 2 brains working for a problem is always better than one.