Windows Error

So, when I loaded the patch today 2 of my computers came up with this message.

"Windows Cannot access the specified device, path, or file. You may not have the appropriate permissions to access the item."

Both computers have admin access, are WinXP, I tried rebooting, closed all firewalls, and virus scanners, and I tried opening from the main file rather than the shortcut.

Any suggestions as to how I can make Window's behave?

Thanks

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Edit: I had updated AVG prior to patch and I believe "Resident Shield" was blocking it even with the AVG program closed. I disabled the feature and the game loads now.

Close thread if needed.

how can I disable it?
I need help too!
i wanna disable the feature only i now have to re download the game -_- fking 4hrs becoz of the AVG healed my "virus"

I get the same message and AVG tells me this:
"Threat detected!
File name: MapleStory.exe
Threat name: Virus identified Win32/Themida"

For AVG at least, open the interface, choose components, click on resident shield and disable it by unchecking the box. Maple can now be started.