AutoCAD10 has been unforgiving this afternoon,
 
When deselcting with the shift key I accidentally tapped the mouse wheel which is a hotkey for activating 3D orbit.
The computer, with min. memory moved the entire model space UCS a fraction.  Unfortunately I had to close the program and upon reopening the dwg, it had no previous UCS to revert to.
 
CAD tip #6277 explains how to disable it, but I hope someone can tell me if theres a way to precisely orbit back to correct UCS. such as snap or type coordinates.
As Im not confident panning in orbit via the mouse back to position will be specific.
 
....Hmmmm
 
 
 
 
 






How to disable 3D orbit on Shift+mouse wheel?


If you want to switch off the 3D rotate view function (3D-orbit) assigned by default to the combination Shift+wheel (rollerwheel), you can change or disable this assignment in the CUI command.
You can find this function in the CUI dialog under Mouse buttons > Shift+click > Button 3: Transparent orbit (assigned command 3DORBITTRANSPARENT).
If you want to use this combination (Shift + dragging with mouse-wheel pressed) for orthogonal panning in 2D, you need to press first the wheel, then the Shift key. YacobEng2011-03-09 06:16:53

And what is the "correct UCS" in this case?  Is it a particular isometric view or something else?  Have you considered the use of "saved views" to be able to get back to "square 1"?

There were no other saved UCS views that Im aware of,
where would I find a list (or choice) of "saved views"?
 
I was working in model space only with 2D dwgs when I accidentally nudged the UCS.  I guess the correct UCS view is X=90d, Y=0d but I cannot snap to this specific orientation.
 
Any additional info is always appreciated
 

Assuming you want to return to *World* UCS, you can use commands "UCS" then "return" for the default UCS. Then may need to type "plan" then "return" for view to follow the UCS. There probably is a way to get there with fewer steps.

Well Carl that solved my problem.
I had changed the UCS straight after I mistakingly moved it the 1st time but some dwgs in model space didnt revert to normal.
What I needed to do was type "plan" then "world" for the view to follow the UCS.
Now the viewports reflect what is drawn in model space....
 
Thanks a bunch!