Problem:
Associating .acu extension with 32-bit 9.1.0 Runtime is not working on 64-bit Windows.
The installation was made from the 9.1.0 64-bit ACUCOBOL-GT archive as there was a need for 64-bit AcuXDBC. However, the COBOL application requires the 32-bit Runtime.
When double-clicking the .acu program file it gives an error about a missing Runtime license. There are licenses for 64-bit AcuXDBC and 32-bit Runtime.
The Windows file association was made again manually and specifying .acu files open with C:\\Program Files (x86)\\Micro Focus\\Acucbl910\\AcuGT\\bin\\wrun32.exe. However, when double-clicking the .acu program file, Task Manager shows that it is still starting the 64-bit Runtime in C:\\Program Files\\Micro Focus\\Acucbl910\\AcuGT\\bin\\wrun32.exe.
Resolution:
The file association apparently only takes the executable name and then gets the path from the registry entry here:
HKEY_CLASSES_ROOT\\wrun32.exe\\Shell\\Open\\Command
To resolve start regedit, navigate there, right-click on (Default) and select Modify, then change it to:
"C:\\Program Files (x86)\\Micro Focus\\acucbl910\\AcuGT\\bin\\wrun32.exe" "%1"