Does this happen only to Windows Explorer?
What anti-virus, anti-syware, do you use? If their definitions are uptodate, do a complete scan for malware.
What processes are running in the background? Right click the Taskbar, select Task Manager then click the Processes tab. Then go to this site;
http://www.answersthatwork.com/Tasklist_pages/tasklist.htm
to check each process against the alphabetical list for strange processes, (eg malware).
What Startup programs do you have? Is there anything there that you do not recognise? (Goto Start > Run, type in "msconfig" without the quotes and check the Startup tab).
What changes have you made to your system since yesterday? Can you use System Restore to go back to a date before today,before the problem started?
Do you have a firewall?
Is your Windows upto date?
Mark
Today, windows explorer started using several minutes befor it shows the content on my disks. Nothing has been changed by me.
Have anybody else encountered this, and is there an explanation?

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