+ 1 Votes have you tried the USB sticks on a another computer? markp24 2 years ago Hi have you tested the usb stick on another computeR? have you tried formatting the drives from that machine? check power saving settings in the bios? (i doubt it, but see if these some power saving feature on the usb ports, and disable it) + 0 Votes Toshiba C650 problems tazyx January 3, 2013 at 4:55pm PST Hi, Check this out: http://forums.computers.toshiba-europe.com/forums/thread.jspa?threadID=65584 http://forums.computers.toshiba-europe.com/forums/thread.jspa?threadID=65823 http://forums.computers.toshiba-europe.com/forums/thread.jspa?threadID=65835 They have problems with MB, implementation of chipset is POOR .... "I got a bad news for you, C650 has a little problem. It suhtsdown the USB ports to prevent over current damage, but C650 do this too early, so if I were you, I take it to an ASP for motherboard replacement.The revisioned one works fine." Go to change MB if it is still in warranty. If not ... buy other brand (Acer, Asus, Lenovo, MSi). Good luck. + 1 Votes Is it possible your stick or system is going into auto sleep? LocoLobo 2 years ago This hasn't happened to me with a stick. But it has with several USB HD. You might check the power settings. + 1 Votes Conflict USB or FireWire Drive Letter Peconet Tietokoneet Updated - 2 years ago http://www.mydigitallife.info/change-or-delete-system-drive-letter-via-registry-to-remove-conflict-usb-or-firewire-drive-letter/ + 1 Votes This is going to sound strange but .... Awahili Guni 2 years ago Some computer manufacturers are coy! They may display an OS (won't matter if it is a Win, Mac, or What-Not - with as many as 6 to 8 USB ports just to lure a buyer. Sadly, in this case "LET THE BUYER BEWARE" - ask tons of questions upfront! What you see is not what you always get; Let's put it this way, supposed you purchased an OS with 6 USB ports in back plus 2 in front. WOW - what a steal! Is it really? What really is behind all of this is the major problem: You could end up with having 2 USB ports which are the Main Core USB ports, the other 4 being the Sub-Ports (in the back); while those in the front are "limited access USB ports with limited of you-name-it". It is exceptionally good idea to ask the salesperson to death tirades of question even if he/she is unable to provide you info or data; then make him/her go to the Tech Department and get that info before you buy! (After all - it is your $$$ isn't it? How would you like for me to sell you a huge Hotel in Las Vegas with a nice sandy beach front with a fully loaded Marina where Millionares can park their Yachts? Get the idea? Don't be fooled with what all is in the "specs" or aka info. WHY? Specs (Specifics) aka Info, doesn't always provide you all the info you need; they just provide you specs to get you drooling just as a Used Car Salesman would sell you that Lexus but won't tell you that there's a cracked engine they welded nor would they tell you that they had welded some other parts with hopes that you wouldn't take it to the Tech of YOUR OWN for inspection but of theirs if you did elect to do so ... for want of an illustration. One option is - finding that "Main USB port" is the issue; usually unless yours was custom built, one can find out via the Manufacturer; if they are honest enough to tell you where 2 or 3 or if you are lucky you have 4 (on newer models) if it is a desktop. Try the connections there and see what happens - whether it be hooking up your camera to USB port to a flash drive; trying various things will let you know this is a main USB port. If Printer to Digital Camera works on it and some of the Flash do, except one. The chances are the Flash has gone D.O.A. (I'm sorry to report that - I've had some 32 GB and 64 GB Flashies that have passed away and have learned that "name brands" are no different than "generics", in fact, my generics have superceded in the lifespan of the name brands which I find that a little bit ironic.) Give this a shot and see how it goes I am going to make another post of another two options you can do + 1 Votes Two Options you can do: Awahili Guni 2 years ago In Win Vista / Win 7 Go to Start, in Search - type in "command.exe" (without the quotes) - once it comes to manifestation - right click and run as Administrator and a pop-up will appear. Type exactly like this without the quotes "sfc/scannow" - if this is the first time you have run this feature, it will take some time; this will repair everything in the Windows from registry to whatever and yet, you can be online or offline and do whatever you need to do while it's running in the background. (Doesn't take much resources, but I do strongly recommend that you first clear cache files, temp files, run the disc/disck clean up, etc first.) Once it has been completed it will provide you notifications if you had any errors and the specs on this, for example - integrity errors were found and were repaired. (Just for an illustrative purpose) I do recommend people to reboot as soon as you complete this, and above all things - keep your OS up to date always! ========================================= If all else fails - while I am only a Windows Certified here and I cannot speak on Mac or other OS Systems - I can advise you the other option is for XP (Microsoft is disconitnuing support here), Vista, and 7 is: Going to Control Panel to Device Manager and delete ALL USB port related hardware found on the list after you have backed up and created a System Restore first. Windows automativally will detect and reinstall - this usually resolves the issue 98% of the time. At the last resort - is going to Microsoft "Fix-It" (clicking on Windows - select your OS - and then select hardware - install the program and allow Fix It to resolve this issue. =================================================== < b> TO THE ORIGINA POST APPLIED ABOVE: I do want to make an admendment for I realized I forgot a sentence: It is generally a good idea to contact your OS Manufacturer, either via their website of if you have the info handy that came with your OS; then give them a call first. </ B> <i> I hope all this helps! And good luck and do keep us posted!</ i> + 1 Votes Could be power. Alpha_Dog 2 years ago USB devices pull a good bit of power. You need to check all the combination of devices in another computer. If it works on the other computer, you may wish to try installing a powered USB hub or replacing the power supply to the laptop. + 1 Votes there was a solution for this problem Kerah 2 years ago this solution enabels me to use the usb sticks for longer time but not much time - i made a small edit to the registry under HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices i removed all the drive letters which not existing in my system and then it works fine but not for long time the problem appears again but after more time. + 1 Votes When you make ANY changes to your system through the registry.. Peconet Tietokoneet Updated - 2 years ago You need to reboot your system for the changes to take affect. + 1 Votes If you have your Windows 7 disk handy... Peconet Tietokoneet Updated - 2 years ago You could do a repair. Load the disk in the drive and reboot your machine. Press any key to make it start with the dvd disk. Press the install button. Then look down to the bottom left you will see "Repair", click on this and then select the repair option. OR: Right-click "My-Computer", select Properties. Click Hardware. Open device manager. Find your USB network device. Double-click it. Select the Power tab and clear the "turn this device off to conserve power" checkbox. Hope this does the job for you. + 1 Votes USB assignments ITOdeed 2 years ago I have a Toshiba A205 running Vista HP with four USB 2.0 ports, and this USB assignment problem happens to me on one of my ports when I reboot the laptop. However, the USB port doesn't disappear. It is assigned a different drive letter. It was originally assigned drive letter F, but after each reboot Vista reassigns it to E. This phenomenon happens when an item in one of used ports is unplugged and the laptop is rebooted while the item is unplugged.