Sorry for the campaign game problem.  You can fix it in 5 steps. Here is the fix for ongoing campaigns: 1.  Get out of KSP and make a copy of your persistent.sfs file.  Name it persistent.ett 2. Open your persistent.sfs file in a text editor. 3. Search for "antennas1".  You should find a section that looks similar to this:         Tech         {             id = antennas1             state = Available             cost = 15             part = SEP.MAG          
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