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#11
You may go ahead with Kaktussoft's instruction/s.
I am just curious to know as to when this problem started. If none of the suggestions work, you may try to restore your system to a point before this problem surfaced.
No, in normal boot problem still exists
So you were able to make it work in safe mode. usb and dvd has drive letters then. After that you did reboot normally. Drive letters were gone then? Reboot to safe mode... still gone?
Second test: Boot to safe mode and give usb and dvd a drive letter. Reboot again to safe mode. Drive letters are still active and working?
In safe mode (after assigning drive letters succesfully) enter "command prompt":
In normal boot mode enter "command prompt":Code:reg export HKLM\SYSTEM\MountedDevices d:\safeboot.reg
Post d:\safeboot.reg and d:\normalboot.reg. You may delete the 2 files afterwards.Code:reg export HKLM\SYSTEM\MountedDevices d:\normalboot.reg
Boot normal boot and safe mode use registry key HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices for drive letters. Something in normal boot removes them?! So win7 can read/write/delete to that key.
You logged in as same user in safe mode an normal mode?
It looks like something is monitoring registry key HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices and does nasty trick.
Try a clean startup Troubleshoot Application Conflicts by Performing a Clean Startup same problem?