The program installation module of Yast is no longer working (clicking on the icon makes a window flash up and disappear a split second later). If I am running it correctly from the command line, I get:

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lnebrown@linux:~> su
Password:
linux:/home/lnebrown # yast2 sw_install
No such client module sw_install

Run 'yast2 -h' for help on usage
linux:/home/lnebrown # yast2 sw_single
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
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so I thought I would just reinstall it, but being the noob that I am, I don't know how or what to reinstall.

Any help would be appreciated,

CLB

Boot from your installation CD. There is a recovery function that should help you reinstall the YaST packages. I've not had the misfortune of needing it yet, but it should be fairly straightforward.