QGIS Not responding - qgis-bin.exe or qgis-ltr-bin.exe not responding

In QGIS, when I double-click on a layer to display its properties (or even right-click to select Properties), QGIS stops responding giving an error message "qgis-ltr-bin.exe is not responding". Was running QGIS 3.10, then uninstalled it and installed QGIS 3.16 Hannover. Problem persists giving the error message "qgis-bin.exe is not responding". I realize my question is similar to previous questions, but have been unable to find the solution to this problem. The problem only started last week.

Is it possible that the problem is related to missing .dll files? Tried running the qgiscrashhandler.exe, but the software is unable to run due to missing Qt5Gui.dll (QGIS 3.10) or Qt5Widgets.dll (QGIS 3.16).