I find it quite funny that one of the ‘solutions’ to this problem is…don’t lock your computer (“you can prevent this behavior by not locking the computer when printing or exporting”). Thanks a lot! Revit is now telling us what we can and can’t do people! (Or, more correctly, the Revit support staff are telling us.)

This shows that you must give Revit What Revit Wants – or it will make your computer unresponsive!

Issue
You print or export your project in Revit and lock the computer during the progress to find Revit is unresponsive when later unlocked.

  1. Solution
    This occurs when Direct3D® Hardware Acceleration is enabled and the computer is locked > Ctrl + Alt + Delete > Lock Computer. There are two options to prevent Revit from becoming unresponsive when printing or exporting:
    Disable Hardware Acceleration through Options > Graphics > Graphics Mode. Un-check Use Hardware Acceleration (Direct3D). This will prevent Revit from going unresponsive when the computer is unlocked.
  2. If disabling Hardware Acceleration is not an option, you can prevent this behavior by not locking the computer when printing or exporting.

From http://usa.autodesk.com/adsk/servlet/ps/dl/item?siteID=123112&id=13855078&linkID=9243099&CMP=OTC-RSSSUP01

This has been reposted from http://usa.autodesk.com/adsk/servlet/ps/dl/item?siteID=123112&id=13778933&linkID=9273944&CMP=OTC-RSSSUP01

Published date: 2009-Aug-21 ID: DL13778933
Applies to:
Autodesk® Revit® Architecture 2010
Autodesk® Revit® MEP 2010
Autodesk® Revit® Structure 2010

revit_2010_wallmodification_hotfix_x32.zip (zip – 7584Kb)

revit_2010_wallmodification_hotfix_x64.zip (zip – 10224Kb)

revit_2010_hotfix_wall_modifcations_readme.htm (htm – 58Kb)
This hotfix addresses issues related to deleting or modifying walls, a crash may occur.
Make sure to download the correct patch for your operating system (32 or 64 bit).
The Readme contains the latest information regarding the installation and use of this update. It is strongly recommended that you read the entire document before you apply the update to your product. For your reference, you should save the Readme to your hard drive or print a copy.

EDIT May 2012

I recently had this issue after reinstalling graphics drivers and using Revit 2013.  I followed the tip on this Autodesk page to run Revit on the primary Windows monitor – this fixed the problem for me.  You can then drag the Windows 7 toolbar to the secondary monitor if you want max screen real estate on your Primary…

EDIT 3/2011
This issue is still annoying some users.  There is a very comprehensive set of comments over at:

http://do-u-revit.blogspot.com/2009/10/whos-dragging-my-stuff.html

A few different solutions are mentioned at that page.

One of our users experienced a very unusual error today. It seemed to appear randomly (no known cause). But it had happened to him before…

Basically, when any object was selected in Revit, Revit would interpret this as a ‘drag’ command, and the object would be moved upward by a certain amount (about 5% of the screen).
We ruled out Direct3D and mouse problems.

However, when logging in as a different user, the problem wasn’t there! So, we reasoned, it must be a user specific setting.

I deleted the UIState.dat file, as Autodesk Support had told me to try this for a different problem. How do you do it? See below quote from Autodesk Support:
To fix the issue, the UI state can be reset to default settings by removing the UIState.dat file by browsing to the appropriate product folder located in one of the following locations:
· For Windows® XP: %USERPROFILE%Local SettingsApplication DataAutodeskRevit
· For Windows Vista®: %LOCALAPPDATA%AutodeskRevit

However, this DID NOT fix up the click-drag problem.

I then went to the registry:
HKEY_CURRENT_USERSoftwareAutodesk
and exported all of the Revit subtree (for backup purposes).

Following this, I deleted [HKEY_CURRENT_USERSoftwareAutodeskRevit] and all the sub-components.

Amazingly, THIS FIXED the issue!!

I am obviously quite happy with this result. Please use this fix at your own risk.