[OS X TeX] DVD must be mounted to install TeX … but it *is* mounted

[Art Werschulz]

Hi.

The 2012 TeX Collection DVD arrived today.  I installed the new TeX on our Departmental Linux machines and MacBook, with no trouble.  I brought it home and slid it into the drive of my desktop unit (an iMac running Mountain Lion).  I double-clicked the installer, and got an alert box saying
   Install DVD Missing
   The TUG TeX Collection DVD must be mounted to install TeX
Say what?  How could I double-click the icon if the disk hadn't been mounted?  Moreover:
   agw at home:~$ mount|grep -i tex
   /dev/disk2 on /Volumes/TEXCOL2012 (cd9660, local, nodev, nosuid, read-only, noowners)
What is going on here?

Art Werschulz (8-{)}   "Metaphors be with you."  -- bumper sticker
GCS/M (GAT): d? -p+ c++ l u+(-) e--- m* s n+ h f g+ w+ t++ r- y?
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