Windows 7
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Pen drive not accessible in windows 7
Recently something has changed on my laptop so I can only view the contents of pen drives and sd cards etc if i restart the computer with them already connected. If I connect external storage devices while Windows is running they appear in "computer" but when you click on them to open them you get the message "x:\ is not accessible access is denied" where x is the drive letter. Please can someone help? Thanks
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What is, if the pen drive is not connected? Do you see the X:\ drive?
It looks like that the device tries to connect to a drive letter, which is associated with another device?
You may try to change just the drive letter (if present without the device), otherwise when the device is connected.
It looks like that the device tries to connect to a drive letter, which is associated with another device?
You may try to change just the drive letter (if present without the device), otherwise when the device is connected.
No, if the drive is not connected it is not visible in computer, as you plug it in you can see it appear and it goes away as soon as it is disconnected
That means first, that the accociation between device and the drive letter is not overlapped.
Removing the device completely and reinstalling helps mostly...
But wondering, what changes to your laptop? Any new software or updates.
Sometimes virus scanners / desktop firewals may block devices, just to exclude this issue, you may turn them all off for a moment and try again.
You may also try to use another USB port.
As drivers are installed on each USB port, it may behave different.
Removing the device completely and reinstalling helps mostly...
But wondering, what changes to your laptop? Any new software or updates.
Sometimes virus scanners / desktop firewals may block devices, just to exclude this issue, you may turn them all off for a moment and try again.
You may also try to use another USB port.
As drivers are installed on each USB port, it may behave different.
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If you are a member of a domain, removable media may have been disabled by group policy
No this computer isn't a member of a domain. I have tried some other pen drives and tried all the usb ports with the same result, also tried turning firewall and anti virus off but it makes no difference, I'm guessing that I need to change something in the registry?
OK, and you said, that it happens with different devices, right?
So not directly connected with a single device?
Is there any device, what works?
And also I interpret, that it worked before....
So the following questions, refer to the numbers to aswer them
1.) Can you get at least one USB device to get run (other sticks, camera or whatever)
2.) Does the stick run on another computer?
3.) Have you installed some software you can connect with this behaviour?
4.) Is your system up to date, all SP / patches?
The question is, if it doesn't work in general, what may be a result of a software installation, software configuration, driver corruption or is imported from somewhere else...
or if the issue is connected with a specific driver, which is used in connection with this device, or a problem with the windows driver, which is used to access such devices.
For the drivers, you may go to Computer Management - System Tools . Device Manager, there you should find your device and can have a loot at the driver details.
Most of the devices uses WpdFS.dll (6.1.7600.16385) and WUDFRd.sys (6.1.7601.17514). These are general windows driver and I wrote my version numbers behind it, should be the same if updates are installed. There may be more than these two.
The other option may have a look at
HKLM - System - CurrentControlSet - Control - StorageDevicePolicies
if you can find this key. If not, fine..., If yes, you may delete the key and try again.
So not directly connected with a single device?
Is there any device, what works?
And also I interpret, that it worked before....
So the following questions, refer to the numbers to aswer them
1.) Can you get at least one USB device to get run (other sticks, camera or whatever)
2.) Does the stick run on another computer?
3.) Have you installed some software you can connect with this behaviour?
4.) Is your system up to date, all SP / patches?
The question is, if it doesn't work in general, what may be a result of a software installation, software configuration, driver corruption or is imported from somewhere else...
or if the issue is connected with a specific driver, which is used in connection with this device, or a problem with the windows driver, which is used to access such devices.
For the drivers, you may go to Computer Management - System Tools . Device Manager, there you should find your device and can have a loot at the driver details.
Most of the devices uses WpdFS.dll (6.1.7600.16385) and WUDFRd.sys (6.1.7601.17514). These are general windows driver and I wrote my version numbers behind it, should be the same if updates are installed. There may be more than these two.
The other option may have a look at
HKLM - System - CurrentControlSet - Control - StorageDevicePolicies
if you can find this key. If not, fine..., If yes, you may delete the key and try again.
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since it happened recently, a system restore to a date it was ok should help you out quickly
otherwise, safely remove is a very good tool for USB problems : http://safelyremove.com/?pid=1
otherwise, safely remove is a very good tool for USB problems : http://safelyremove.com/?pid=1
Hi Nobus, I can't say for certain when the problem first started and have installed a lot of software recently that I don't want to re-install so system restore isn't really an option, I have downloaded the safely remove software that your link pointed to but it didn't make any difference and is only a 30 day trial so I will probably download it later and stick to the Windows version. Thanks anyway
Hi Bembi
Here are the answers your questions
1 Yes my Blackberry works ok when I plug it in but no pen drives or SD cards will work
2 Yes all the pen drives and cards work on other computers
3 I am fairly certain that none of the software that I've recently installed could have caused this problem as my most recent software is either browser related or Open Office and the pen drives worked then as I installed this software from one.
4 Yes the system is right up to date with SP etc
5. I am pretty sure the problem isn't driver related because the pen drives work after restarting the computer with them already attached, also it isn't just one make of pen drive as I've tried several different ones and I also get the same problem with SD cards
6. The registry key HKLM - System - CurrentControlSet - Control - StorageDevicePolicies doesn't exist in my registry
Thanks for trying!
Here are the answers your questions
1 Yes my Blackberry works ok when I plug it in but no pen drives or SD cards will work
2 Yes all the pen drives and cards work on other computers
3 I am fairly certain that none of the software that I've recently installed could have caused this problem as my most recent software is either browser related or Open Office and the pen drives worked then as I installed this software from one.
4 Yes the system is right up to date with SP etc
5. I am pretty sure the problem isn't driver related because the pen drives work after restarting the computer with them already attached, also it isn't just one make of pen drive as I've tried several different ones and I also get the same problem with SD cards
6. The registry key HKLM - System - CurrentControlSet - Control - StorageDevicePolicies doesn't exist in my registry
Thanks for trying!
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good luck then - it's your choice
You forgot one querstion about the installed drivers...
Forgot to put a number there...
You may add two environment variable for the system.
devmgr_show_details=1
devmgr_show_nonpresent_dev
after a reboot, you can go to device manager and right click device manager - view - show hidden devices.
You see now even hidden or non present devices, which allows you to uninstall them from the system. As all your devices are hooked into the registry at several places, this procedure may remove struggled associations and you may have the hope, that windows recreated the default settings.
As you said, that you can connect you balckberry, but not all kind of pen drives, it is possible that there is a problem with the type of the device.
You may find your pendrives under disc drives and / or under USB-Controller.
But keep in mind that there may be other devices, even your balckberry, cameras, mouses etc.
To find out, what USB port is connected to which USB-Device, you may have a look into the properties - Details tab. Under the poperties there, you find usually what it is or what is was, or at least a class type.
Removing the known and unknown devices removes the hardware association as well as settings and drive letter assignements. So after you removed them (and rebooted you machine), you may try to see, if windows starts a driver installation, if the devices is plugged in again. As most such pen drives don't have special drivers (non windows), they should be installed again with default settings.
Forgot to put a number there...
You may add two environment variable for the system.
devmgr_show_details=1
devmgr_show_nonpresent_dev
after a reboot, you can go to device manager and right click device manager - view - show hidden devices.
You see now even hidden or non present devices, which allows you to uninstall them from the system. As all your devices are hooked into the registry at several places, this procedure may remove struggled associations and you may have the hope, that windows recreated the default settings.
As you said, that you can connect you balckberry, but not all kind of pen drives, it is possible that there is a problem with the type of the device.
You may find your pendrives under disc drives and / or under USB-Controller.
But keep in mind that there may be other devices, even your balckberry, cameras, mouses etc.
To find out, what USB port is connected to which USB-Device, you may have a look into the properties - Details tab. Under the poperties there, you find usually what it is or what is was, or at least a class type.
Removing the known and unknown devices removes the hardware association as well as settings and drive letter assignements. So after you removed them (and rebooted you machine), you may try to see, if windows starts a driver installation, if the devices is plugged in again. As most such pen drives don't have special drivers (non windows), they should be installed again with default settings.
Hi Bembi, that sounded like such a good suggestion I thought it would definitely work but sadly it didn't, I still think I need to change or delete a registry key somewhere, I've just tried another external hard drive, one that I've never used before, and the problem is still there on every usb port, however I tried a camera and it worked perfectly, but when I took the SD card out of the camera and plugged it straight into the laptop it couldn't read it, so the problem appears to be confined to pen drives, external hard drives and SD cards.
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These devices have all the same type.
Check the drivers as I said, just to exclude, that this is the problem. Drivers may be corrupted or overwritten. Beside this, you may also check the usbstor.inf file, maybe this is overwritten.
Another hint maybe the BIOS, but depend from your laptop. Have a look there, if there is something, what may influence USB devices. As you said, they work when they are plugged in during boot, but do not work when windows is started, it is possible that the BIOS take control over it and blocks windows. Some Bios have a setting about Plug and Play OS, what determines if the Bios or the OS should take control over some devices. It is a try to change this, if present. Nevertheless doesn't change from alone, if it worked before.
Another try would be to logon with a differeren user, if this changes something.
You may search, if there are related updates for your laptop type from the manufacturer, what can be a newer BIOS or even drivers for your laptop. Some vendors use their own drivers for USB devices.
Have a look into the picture to see, how you can find such devices in the registry. You can also seach for the name of the device or a part of it.
But rather than deleting such values in the registry, you should uninstall them all, and then try to seach the registry, if there is something, what is left over. Nevertheless there are some default registry keys for some special devices, so don't delete something, what you are not absolutely sure, what it is. YOu will even find some devices, which never where connected to your computer as MS puts some special devices into the registry to make them work without additional impact.
Check the drivers as I said, just to exclude, that this is the problem. Drivers may be corrupted or overwritten. Beside this, you may also check the usbstor.inf file, maybe this is overwritten.
Another hint maybe the BIOS, but depend from your laptop. Have a look there, if there is something, what may influence USB devices. As you said, they work when they are plugged in during boot, but do not work when windows is started, it is possible that the BIOS take control over it and blocks windows. Some Bios have a setting about Plug and Play OS, what determines if the Bios or the OS should take control over some devices. It is a try to change this, if present. Nevertheless doesn't change from alone, if it worked before.
Another try would be to logon with a differeren user, if this changes something.
You may search, if there are related updates for your laptop type from the manufacturer, what can be a newer BIOS or even drivers for your laptop. Some vendors use their own drivers for USB devices.
Have a look into the picture to see, how you can find such devices in the registry. You can also seach for the name of the device or a part of it.
But rather than deleting such values in the registry, you should uninstall them all, and then try to seach the registry, if there is something, what is left over. Nevertheless there are some default registry keys for some special devices, so don't delete something, what you are not absolutely sure, what it is. YOu will even find some devices, which never where connected to your computer as MS puts some special devices into the registry to make them work without additional impact.
Hi Bembi I don't think it's drivers because I get the message device driver software installed successfully, also if it was drivers I don't think the pen drives would work at all and they do. I'm not sure how to check the usbstor.inf file to see if it has been over written and wasn't sure what you meant by "have a look into the picture" maybe you could get back to me on those. Thanks
USBstor.inf
just have a look, when it is changed, but USB drives also may install there own inf files.
In the picture (the one I forogot to attach) you find them as well somewhere.
The picture gives you an idea, for what to search in registry and if there is something left over. But as I said, there are some default components installed by the OS. But you may identify your device.
You said, after you uninstalled them, there is a installer message and the device installs. Cann you access it just right after the install? Also you can click on the message to see, what they install and if this was successfull.
The other option maybe, as BIOS can regognize USB drives as well, that just one of the services ist not running, like SSDP, Access to input devices UPnP? Just check if all services are running, which are set to automatic and you may try to start some of the services above, just to see, if this is the reason. As I said, Bios can discover them, but if not plugged in during boot, windows has to discover them.
devices.jpg
just have a look, when it is changed, but USB drives also may install there own inf files.
In the picture (the one I forogot to attach) you find them as well somewhere.
The picture gives you an idea, for what to search in registry and if there is something left over. But as I said, there are some default components installed by the OS. But you may identify your device.
You said, after you uninstalled them, there is a installer message and the device installs. Cann you access it just right after the install? Also you can click on the message to see, what they install and if this was successfull.
The other option maybe, as BIOS can regognize USB drives as well, that just one of the services ist not running, like SSDP, Access to input devices UPnP? Just check if all services are running, which are set to automatic and you may try to start some of the services above, just to see, if this is the reason. As I said, Bios can discover them, but if not plugged in during boot, windows has to discover them.
devices.jpg
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Hi, the inf file always shows the current date and time when I check to see when it was last modified, the pen drives always install correctly and appear in device manager as a disk drive but in "computer" they just show as a "removable disk" (instead of having their usual name) and will not allow you to open them even just after they are inserted. I had a look in the bios and tried changing a few things but nothing improved. I think it must be registry related but not sure what key is causing the fault.
UPDATE: I have tried again in safe mode and the pen drives work properly, thinking that this was anti virus related I have tried turning Kaspersky off again and restarting normally but this made no difference apart from dramatically speeding up my computer!, I think I am close to finding a solution and I could go through the list of services and start up items and turn each one off individually and keep restarting the computer to find the one causing the problem but I don't have time to do this today so I will give the points to the peerson giving the right answer if they can identify which service or start up item is causing the fault. Thanks
did you look in event viewer? problems are listed there
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This is the only solution that worked
Windows 7
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Windows 7 is an operating system from Microsoft. Features include multi-touch support, a redesigned Windows Shell with a new taskbar, referred to as the Superbar, a home networking system called HomeGroup, and performance improvements.