Cannot install JDK 9 because "another Java installation is in progress"

Question

I have been using JDK 9 on Windows 10 x64 for a while, but when I went to install the latest early version (b174), I first uninstalled the previous version (as usual) and then launched a new installer.

Failure to report that "another Java installation is in progress. You must complete this installation before you can run this installer."

There seems to be some artifacts around the problem, but only for JDK 9, since I can remove and reinstall JDK 8 without any problems. Also, the same problem occurs if I try to run installers for any previous releases of JDK 9 (even if they worked before).

Search queries offered various options, such as using the Microsoft MSI cleanup tool and registry, but nothing helps.

Can anyone suggest a way to install JDK 9 (since now I can’t use any release of JDK 9 at all)?

Answer 1

On Windows, Java prevents the installer from running twice by creating (two) lock files. If these files exist, the Java Installer displays the message: "Another Java installation is in progress (...)."

If the Java installer crashes or Windows crashes during the Java installation, the installer cannot delete the lock files at shutdown.

Decision:

Removing lock files, unlocking the installer and Java can be installed again.

Lock files are located at:

C:\ProgramData\Oracle\Java\JAVA_INSTALL_FLAG % USERPROFILE%\AppData\LocalLow\Sun\Java\JAVA_INSTALL_FLAG