Incorrect learned path

[Robert Rivkin <rrivkin@umbc.edu>]

I seem to remember this having been discussed several 
years ago, but I don't remember the solution.

The problem: sporadically, when working on my friend's 
hard drive [which is now happy on his Apple HiSpeed SCSI 
thanks to all of you who helped with that problem], I cannot 
double click on a file in the finder to open it.  In fact, 
clicking once does not highlight it.  Clicking twice [on 
any file that doesn't highlight] boots the RamFAST System.

If I use the arrow keys, I _can_ highlight the file, then open
it by double clicking on it.  

I remember having done something similar many years ago, and
I can't remember the solution.  Help?  Ideas?

TIA,

Bob