"losing" the program doesn't impact the data.

Have you lost the program, or just the desktop icon isn't working?

Windows 'start' button > Programs > Lacerte 2021 = click on that to see if it opens.  

And/or (same steps) Lacerte 2021 WebSetUp.  Force install even if *it* says all is OK.  

Again - this doesn't NOT impact data (assuming it hasn't gone away previously for some unknown reason).