If you are on the server, or using a standalone, just use C:\Lacerte\18tax\Setup18\Taxsetup.exe /Force
Copy this text > C:\Lacerte\18tax\Setup18\Taxsetup.exe /Force
Press the Windows key + R (at the same time)
In the Open: window you may see some other text, just paste what you copied in that box and press enter
In the future, be careful of how the wonderful posts your question - We are "Lacerte" without all the added verbage of ProConnect Lacerte - Your question seems to have posted for the online version, in which case look at the answer below