[DM-MUG] Problem with System Preferences (10.4.11)

[Russ & Marilyn Carlson]

I am using 10.4.11.  I am still using dial up and went to change to  
some new telephone numbers.  I went to system preferences network and  
a sign pops up that says "Your settings  have been changed by another  
application".  When I click on the OK button it goes away momentarily  
but comes right back.  I can't do anything else in the network and I  
have to force quit in order to close system preferences.  Does anyone  
have suggestions?

Russ