Normally, double-clicking a .bat file's icon (or a shortcut to the same) should open a command processor window and run that batch file there. Now the command processor window opens, but the batch file does not run. (But the batch file does run either after I type its name at the command line in the window, or if, instead, from the Start Menu I use Run and in the "Open:" input box type:
cmd /c path_to_bat_file\batch_filename.bat
How can I reassociate batch files with the default Window API action?
I tried the standard approacyh of going to Tools > Folder Options File Types and associating .bat files with type MS-DOS Batch File and specifying that .bat files should be opened with Windows Command Processor. But that does not correct the problem.
I also checked the Registry. In HKEY_CLASSES_ROOT, the entry for .bat gives under key PersistentHandler a CLSID that has under its own key PersistentAddinsRequired a subkey that points to a CLSID whose subkey InProcServer has two subkeys: (Default) with value query.dll and ThreadingModel with value Both.
Note that this behavior appeared after I installed JP Software's 4NT command processor and opted to make it the default processor for command prompt windows. However, I have since uninstalled 4NT.