I hope somebody can help me retrieve my file from this mayhem.A very important drawing file I've been working recently and when I tried to open the file again to continue my work, the entire composition suddenly been change into some kind text reading "MUST re1/8cover!" and I can't change it back into its former state. I've done all types of recovery process in Autocad way, I also tried various types of anti malware and viruses utility but still none of it was effective. I didn't know what happened , and I am no expert in cad because I only study it all by myself. Please help me find solution to this problem. Thanks!!!

Do you have a *.bak file?
 
You may be able to rename the *.bak file to a *.dwg file.
You will lose any changes you made after the *.bak file was created.
 
Lets hope you have a backup file.

This is a result of the acad.vlx virus. See also:
http://www.cadforum.cz/cadforum_en/autocad-displays-must-re_cover-tip7384

For the " Tankman ",I had that procedure first thing in my mind way since from the very first incidence because I have my option set in auto-save mode that supposed to work automatically in every 15 minutes but when I tried to change the drawing back-up file( *.bak ) to cad drawing format (*.dwg) it doesn't open normally, a message appeared that the file wasn't not supported at all. But anyway man, thanks for the tip, I do really appreciate the concerns included within. I think I should look for Vladz tip and look what I could extract there that could do good that concerns with my misery.Again Thanks!Culangot2010-06-02 16:49:31

I'm sure  Vlazd's tip is probably the best.
He knows.
 
I too had trouble changing a *.bak file to a *.dwg file.
 
Solved the problem at the DOS prompt, file where the *.bak file is; i.e.:
 
CADFORUMCZ.bak ren CADFORUM.dwg.
 
"ren" is short for "rename".
 
Close the DOS prompt. Back to Windows and AutoCAD. The newly renamed file opened without a problem.