Test page prints but apps appear to hang while printing

[rod]

I have redhat 7.3 with a parallel port HP1200 laserjet. Recently, we had a hrd disk failure and after a hardware switch, we could no longer print from KDE apps -- they hung.  But we could print using lpr from the command line.

A "helpful" self-styled Linux expert went into CUPS admin and deleted the printer.  I followed the CUPS instructions and reinstalled. Seemd quite straightforward and I can print a CUPS testpage fine from the admin web interface but when I attempt to print from an app, the app hangs.

As well the command line cmd "lpinfo -v" just hangs.  All the nice gui tools like kprinter and the gnome printer manager all hang when we try to actually do anything.  Gnome sometimes responds that CUPS is not available.  Ooops, while making this posting kprinter just popped up -- 20 minutes after the print command was started in Kate.  I pressed PRINT and now we are back in pseudo-crash mode.... hmmm

In the the absence of any meaningful diagnotic messages, I have not been able to find any documenation that might help me some kind of troubleshooting diagnostic.  Any suggestions where to look?  And I am an old UNIX/Linux admin, but CUPS is new to me from an admin point of view.

Suggestions please?

Rod