A java error came up in the middle of a standalone Primavera P6 install for a client. We had just finished installing SQL 2008 and were running the database setup. When we would go to launch the database file we received the error: “unable to access jarfile lid\dbmt.jar” We examined the batch file, tried re-naming the pointed directories, modifying java settings, re-downloading Primavera P6 install files, and a host of other things. Nothing worked and we put the project on hold until the next day when it could be approached with a clear head. Thankfully, we were able to solve the problem when we resumed in the morning. The fix? Change your windows preferences to un-hide the “hidden folders.” Even though the java (jar) files were on the computer, they were hidden, and the batch file couldn’t run, which produced the jarfile and java home errors. Once we changed the setting, the install worked perfectly.
To unhide your windows folders:
Open Windows Explorer
On your keyboard press the Alt key
Go to Tools —> Folder Options
On the View tab, under Files and Folders, Click the bubble for “Show Hidden Files, Folders, and Drives”
Full disclaimer that this fix won’t remedy all java errors in Primavera P6 installs. Unhiding the folders worked in this case, but other times we have seen not-fully unzipped install files and corrupt java files to be culprits. We suggest re-installing and un-zipping the install files if unhiding doesn’t work. Unfortunately P6 installs can be tricky, we hope this helps. Good luck!