Dot Net Framework
Dot Net Framework can fail due to Microsoft updates, and countless other things.
Use this utility to uninstall Dot Net Framework.
Follow this link.  In the third paragraph down, see the blue words, this link.
Select it and run it.

When it's all done, and it can take awhile, reboot your PC then go here:
Click on this line to download and then install Microsoft Dot Net Framework, again.
This can take 30 minutes, once it begins.

Reboot your computer, try the software. 

If you are using Quickbooks, then QuickBooks will stop working.  To correct this, you need to run the QuickBooks repair utility.  Go  to the Control Panel, select Add/Remove Programs.  Select Quickbooks, Remove.  In a few moments, you will be offered the QuickBooks Repair option.  Select Repair, and follow the prompts.  This may take an hour, but again, our personal experience has always been positive.  Tip:  Start the process, then walk away from the computer.  It may hang up, then it will continue.  Be patient.  You will not lose any data (!!) by doing this.

We have used this. It worked for us with Quickbooks issues, and has worked for us with TimeSource and TimeVue issues.  Other MCSE technicians are familiar with this procedure. We do not know if it will work for you, and do not offer further support, or guarantees, on this.  In the end, you may need to call Quickbooks Support at 1(866) 340-7267, but we have not had to.

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