U Nothing to undo .... WHY CAN'T UNDO PREVIOUS COMMAND WHAT CAUSE THIS PROBLEM?

What command were you trying to undo?

lines only some basic command then i want to undo the previous work nothing has undo nether one command

How can you use the UNDO command since your thread title clearly states MISSING UNDO COMMAND?If it is missing then you would receive an "Unknown command" error message.BUT....you say that you run the UNDO command (can't be missing then can it?) and receive the message "Nothing to undo".  Which means the command IS working but there is.......................wait for it.......................NOTHING TO UNDO!  AutoCAD is saying it has gone as far as it can to undo previous work.  Did you check to see what the system variable UNDOCTL is set to?Read this to learn more about this system variable....http://docs.autodesk.com/ACD/2010/ENU/AutoCAD%202010%20User%20Documentation/index.html?url=WS1a9193826455f5ffa23ce210c4a30acaf-4e17.htm,topicNumber=d0e358937
John Connor2015-11-24 14:33:32

UNDOCTL 53 reads sir

Same as my system.  I guess there wasn't anything left to undo.  Move on.

Are you trying to Undo work from a previous editing session, as the first thing you try to do when you open a drawing?  It does not keep track of operations once the drawing is closed, so that will not be possible.  If this is not the first thing when opening a drawing, then you must have dumped all Undo information, such as with UNDO / Control / None.