Start with the Overkill command.  You should be in the Drafting and Annotation workspace.  Look on the Home tab > Modify panel for an icon that looks like a broom.

OVERKILL
Removes duplicate or overlapping lines, arcs, and polylines. Also, combines partially overlapping or contiguous ones.

Next run the command line version of the Purge command.  This is preceded by a dash so it look like this: -purge.

Purge Regapps first.  Repeat the command but this time select the All option.

PURGE
Removes unused items, such as block definitions and layers, from the drawing.

Finally, run the Audit command and when AutoCAD asks if you want it to fix any errors it finds answer Yes.

AUDIT
Evaluates the integrity of a drawing and corrects some errors.  It does this by examining the drawing's database.

Do a Zoom > Extents then Save your drawing.

I'd repeat the entire process a second time just to be sure you did not miss anything.  If you are still having problems with a drawing then we must take further measures.

Got all that?  Good.  Now go do it.

Why are you even using the PASSWORD feature in the first place?  Do you share a computer with someone else? 

Sounds like a REPAIR of the installation may be in order.  Note that a REPAIR is NOT the same as an UNINSTALL/REINSTALL.  There is no need to go to that extreme.

Just curious though.  Have you done any kind of a cleanup on this drawing file?  Run -Purge command?  Run Audit command?  Run Overkill command?


Edited by John Connor - 12.Sep.2015 at 22:49