Windows 7 Explorer lockup when I plug in external USB drive

[Sheepish]

I have just re-built my windows 7 machine after a harddisk failure. All seems to be working fine except for my external USB drive which locks up explorer and windows in general, only way out is the magic reset (even Task manager locks up).
Any suggestions most appreciated.

 

[Pauli]

Does Device Manager give any alarms?

 

[Sheepish]

Device Manager is clean, no alarms.

 

[Pauli]

It could be as simple a thing as cable issue... Tried another USB port?

What Antivirus are you running? You could try
1. Turning AV and other security programs off
2. Shut down computer and unplug USB drive
3. Start computer and connect USB drive but do NOT start security programs --- you can safely stay for a couple of hours in Internet with Windows 7, there's no imminent danger.

Did the problem arise immediately after the new installation? Did you have anything like this with the previous installation?

 

[Sheepish]

I can use my external USB drive when I start the PC in Safe Mode.
I use Total Defense Security, it has a snooze option I will try to use the drive when I put it in snooze mode.