Hi @Anonymous,
I see that you are visiting as a new member to the AutoCAD Mechanical forum. Welcome to the Autodesk Community!
I am sorry you are having trouble opening files. Are you working with AutoCAD 2016 or AutoCAD Mechanical 2016?
Is the program opening and files are not opening, or is the program freezing before you are able to open files?
Have you received any errors?
If you think it could be a corrupted install, a Reset to Defaults - How to reset AutoCAD to defaults or Reinstall from the operating system - How to repair or reinstall AutoCAD installation may help.
Please note, that for AutoCAD Mechanical (and all Toolsets), there will also be 2 updates to install, one for Mechanical, and one for core AutoCAD.
How To: Installing AutoCAD Mechanical Updates
All the best,
Cheryl Buck
Technical Support Specialist

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