Windows XP
For one user this folder use to be located in %userprofile%\Start Menu\Programs\Startup
Thel users profile the location of the Startup folder is C:\Documents and Settings\All users\Start Menu\Programs\Startup.
Windows 7
Personal startup folder should be C:\Users\<user name>\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup.
The All Users startup folder should be C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup.
You can create the folders if they aren't there. Enable viewing of hidden folders to see them.
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