Just got worse; trying to reinstall it and bombed out, logs shows:
RSLogix 5000 Setup: ERROR: MSXML4 analysis failed attempting to instantiate DOM:
Reason: 80040154: Class not registered
RSLogix 5000 Setup: Attempting to register: C:\WINDOWS\system32\msxml4.dll
RSLogix 5000 Setup: LoadLibrary failed with: 1114: A dynamic link library (DLL) initialization routine failed.on: C:\WINDOWS\system32\msxml4.dll
RSLogix 5000 Setup: Could not register file [C:\WINDOWS\system32\msxml4.dll]
RSLogix 5000 Setup: Rerunning MSXML4 analysis
RSLogix 5000 Setup: Begin MSXML4 analysis on [E:\Software\Rockwell Software - AB\RSLogix5000\20.04.00-RSLogix5000-Web\RSLogix5000\Config\V20.04_web.xml]
RSLogix 5000 Setup: ERROR: MSXML4 analysis failed attempting to instantiate DOM:
Reason: 80040154: Class not registered
RSLogix 5000 Setup: XMLM: MSXML is not functioning so configuration file at [E:\Software\Rockwell Software - AB\RSLogix5000\20.04.00-RSLogix5000-Web\RSLogix5000\Config\V20.04_web.xml] cannot be parsed
RSLogix 5000 Setup: End creating media list needed for edition
RSLogix 5000 Setup: An error occurred during loading