this could be one way to stop it from starting:
Click on Start-Run, type: msconfig, then click on OK. When the System Configuration Tool loads, click on the "Startup" tab, then see if " c:\WINDOWS\system32\cmd.exe" is listed there.. If so, UNCHECK the box next to it, click on "Apply", then restart the machine. Upon restart place a CHECK mark in the box to NOT run System Configuration Tool at startup..
Or you could simply open the registry editor and check for the listing at either the locations below. If so, delete the line indicating such:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
or
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
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The issue may be occurring through one of your programs, I would also download Autoruns
http://technet.microsoft.com/en-us/sysinternals/bb963902.aspx
you can search each entry online, right click for this option
I would scrutinize what you have loading on StartUp. You need to see if you have programs loading during boot process which might be changed to on demand.
With Autoruns you can uncheck an item, which disables it from starting, or you can right click an item and then delete it. If you uncheck you can recheck to re-enable the item. It is a much safer approach than editing the Registry and better than using msconfig.
Another useful feature of the program is that you can right click an item and select Search Online to get information about the item selected.
When using Autoruns you will need to click on the "Logon" tab to see what is running at start-up.
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Also do the following to see if you have malware causing the issue:
Download, install, update and do full scan with these free malware detection programs:
Malwarebytes Free (MBAM):
http://www.malwarebytes.org/products/
SUPERAntiSpyware: (SAS):
http://www.superantispyware.com/
Remove all found, reboot, and run again until scans run clean, these can be removed afterwards if you so choose. Run scans one at a time, please.