Basically what happens:
Install the modem drivers from disc, then insert the USB cable, and then it either freezes, reboots, or blue screens. I've had the ADSL USB modem replaced, it worked fine for a day, rebooted, wouldn't connect, same thing happened. Also, when I leave the USB cable in when booting up, it will not load past the boot screen (but of course I can get into safe mode). My motherboard drivers are fine, other USB devices are fine. And it's not the USB port, I've tried several. It would also do the same issue on another system.
I've tried a reinstallation of the O/S, which was XP Home, now on XP pr0. Like I said, the brand of modem doesn't matter.
However, I noticed that if I delete all the files in "Temporary Internet Files" and "Temp" then I was able to plug in the USB cable, and then connect without any trouble. I have a few screenshots etc.
Those were the files that Windows Error Report or w/e said caused the problem (I get the "system has recovered from" etc message). Therefore, I delete the whole Temp folder (seems to have worked).
Any help would be greatly accepted. Thanks in advanced.