At 06:58 PM 4/30/2010, Larry Gerhardstein wrote:
I have a Keyspan 4-port USB to RS232 box with optical isolators from CommFront
It seems most likely that you have defective driver software for the USB device. That's the most likely cause of this sort of a crash.
I suggest you go to Keyspan's web site and attempt to find the very latest driver. Their web site has a "support" tab with a "downloads" submenu, and finally a "software/drivers" page. Install the latest driver and try again.
One hangup. I just checked their website, and it appears that they have NO drivers listed for windows 7. Perhaps you should call their support folks and ask about this. If they've never tested with Win7, or have known problems, then you may need to give 'em hell. If you can't get a driver they've specifically tested with Win7, then they are officially weenies. At that point you should at least try the very latest Vista driver.
If that doesn't help, buy a different brand. To have the best chance of something that works right, buy the brand which you believe sells in the very highest volume.