The USB-LPT adapter is a Rosewill RCW-615. It has no supplied driver; it uses Windows 7's own usbprint.sys as the interface between the OS and the device.
I am using the latest chipset drivers available for my MB.
Windows loads fine with this driver unplugged, but that doesn't stop it from hanging when the external drive is powered up.
How about the printer. Have you installed its full software?
The adapter isn't supported for Win7. Makes me wonder if it is messing with your USB controller in some way when the external is plugged in. For example, sometimes external will disable USB wireless adapter when plugged into certain hardware due to USB glitch in soft- or hardware.
Are you in a postion where you can move the data off the external, wipe it then reformat NTFS Logical using free Partition Wizard bootable CD? This will eliminate possibility of external causing prob. http://www.partitionwizard.com/download.html
Are there errors in Event Viewer>Admin View or Performance - Diagnostics log at Control Panel\All Control Panel Items\Performance Information and Tools\Advanced Tools which can be googled for resolution?
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