Quartus II not compiling

[Altera_Forum]

When I try to start compilation or start analysis & synthesis nothing happens. 

The compilation report comes up immediately and the Flow status says successful, but the date is wrong. I can even make a blatant syntax error, like getting rid of a semicolon, and the flow status remains the same.  The green check marks in the task menu don't show up anymore.  I did have the project working correctly a few weeks ago. I'm using v13.1. I setup the top level file with a test bench file and use Modelsim to simulate. I can make changes to the files and save them, and then use Modelsim to compile and run the testbench. However, if a want to start a new project I can't compile using Quartus II.  Any suggestions on how to get Quartus to run full compiles again?

[Altera_Forum]

It sounds like the files being used by synthesis are not the files you are updated, and so it's thinking there are no changes. 

 When you setup the Modelsim project did you move the location of the source files???  If that is not the case, my only guess is it's thinking there's no changes. You can try deleting the incremental_db and db directories from the synthesis directory and see if that fixes the problem.  Pete