Thank you all for trying to help.
I had to do a hard reset to undo the problems caused by my frivolous installation of
Internet Sharing FIX.cab.
I then went to the page provided by prochobo, "
How To Enable Internet Connection Sharing On Sprint HTC Touch Pro." This got me to the point where the 2nd drop-down menu on the
Internet Sharing page,
Network Connection, is now being displayed.
But that's where I'm now stuck. I've changed the
Network Connection from
Phone As Modem to
Sprint, but I'm unable to turn on
Data Connection in the
Comm Manager and therefore still can't get rid of the
Error 67. This may be because I'm on a Mac. Also, as z28marols1 pointed out, I'm actually on the Touch Pro forum, when I should be on the Touch (HTC Vogue) forum.
So I'll now go to the correct forum and post there. Thanks, again, for all the attempts to help.