XPS.  Dell Dimension  desktop 4500.   I did add a new Canon printer (although the problem predated that I believe).  No other changes

Here are some things to check

 

1.  Empty the temporary internet files

 

2. Open Internet Explorer.
Choose Internet Options from the Tools menu.
Go to the Advanced tab.
Under Browsing, uncheck "Reuse windows for launching shortcuts." (or similar)
Click OK

I'm having the same issue but sometimes mine won't even reboot-I have to turn off the computer manually. I've tried the suggestions so far and nothing seems to help. I have a Dimension E520. I'm not very computer literate so I'm thinking it may be a setting of some kind but I don't know what. I'm really frustrated with this-makes it difficult to use.

Try this fix

http://www.kellys-korner-xp.com/xp_tweaks.htm

 

Scroll down to line 209 and in the right-hand column, click on the word "New" to download a registry fix.

Once downloaded, double click it, answer "Yes" to the import prompt.