Barabara -

The link check in the immediately preceding post shows that Mustak "frames" their "pages," so that the address bar isn't specific to the article. You need to put your 600CP in to the search box that you get when you select "Support" on the page linked, and then go to the page it finds for the install instructions.

No good ideas on your Items 3 and 4, except that the symptom (going somewhere strange at startup) may relate to the messed up USB port configuration for the scanner. This could also – remotely possible – relate to the crash reported by DMcG.

In WinXP, the "Selective Suspend" routine that allows the machine to shut down "unneeded devices" sometimes gets confused if all the USB devices aren't perfectly sychronised. One thing that sometimes helps is to disable power management for the USB hub.

KB article 315664 suggests, for a somewhat similar problem:
"To work around this issue, disable power management of the USB hub.
"NOTE: Although the following procedure may enable your computer to shut down properly, it may also reduce battery life on a laptop computer.
"To disable power management on the USB hub:
Right-click My Computer, click Properties, click the Hardware tab, and then click Device Manager.
"Double-click the Universal Serial Bus controllers branch to expand it, right-click USB Root Hub, and then click Properties.
"Click the Power Management tab.
"Click to clear the Allow the computer to turn off this device to save power check box, click OK, and then quit Device Manager."

No promises on this last one, but the "go to sleep" functions in WinXP are implicated in several similar "obscure" effects, especially if you have less than perfect setup on USB devices; and unless you have a laptop with short battery capacity, they're not particularly necessary so turning them off doesn't hurt you much. Most of the things that happen are the result of failure to properly save all the Registry entries during shutdown, which means of course that you don't get a "proper boot" the next time you start.

Using the System Restore will replace the current Registry with the one you restore to, so it may "undo" some of the configuration stuff you've gone through. If you want, you can always click "Start - Run" type "regedit" hit Enter, and in regedit click "File - Export" and save the current registry somewhere where the machine can't get to it so that you'd be able to get back to where you are now if you decide you really want to.

John