Run runonce.bat. runonce.bat does a lot of what happens during installation (it re-registers DLLs and SPDLs) and it is a lot faster than removing and then reinstalling Softimage.
To run runonce.bat:
Exit Softimage.
Open a Softimage command prompt (click the Windows Start button, click All Programs, click Autodesk, click Autodesk Softimage 2010 x64, and then click Command Prompt).
On Vista, right click the Command Prompt shortcut and click Run as Administrator.
In the command prompt, run this command runonce.bat
Start Softimage and see if the problem still occurs.
If the problem still occurs, you may want to check if runonce.bat reported any errors. To do that, redirect the output of runonce.bat to a text file. You can do this by running the command runonce.bat > runonce.log. Then you can open the log file and check for errors. If you see a lot of errors, that usually indicates a permissions problem (for example, your Windows account may not have Administrator permissions).
On 64-bit systems, you can safely ignore the error about gl4emult.dll.
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