Windows cannot find "C:\WINDOWS\ eksplorasi.exe"

Attimes, when windows starts up, you get the message -

Windows cannot find “C:\WINDOWS\eksplorasi.exe”. Make sure you typed the name correctly, and then try again.

So this error indicates that there is a missing file needed for windows to start a particular program properly. There is no issue with the startup of the OS. Just delete it from the startup folder in the Start Menu and uncheck the line that specifies it in the 'Msconfig'.Even then if the problem doesnt solve, use 'hijackthis.exe' or manually find the line in the registry using Regedit. Do backup the registry before trying these!!!
Usually you should find the lines in the following paths in the registry:

Computer\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
Computer\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run\RunOnce
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce

Ref: Chip

Note: I suggest you not play around with the registry unless and until you are way too smart than the registry if you know what I mean.