Seems like this is an issue that won’t go away. I had a machine crash. I reinstalled 1.6.8 and it seemed to work except one library (LMXShield from I-SYST) wouldn’t load. It returned a message “not a valid library file.” Spent a couple of hours troubleshooting and decided to re-install the IDE. Found a download for 1.7.1 and installed it. I was able to load the LMXShield without a problem. Unfortunately, I discovered 1.7.1 didn’t recognize any COM ports even though they appear in the Device Manager… (sound familiar???)… followed all the advice I found on this forum for troubleshooting the issue with no luck. Thought it might be a 1.7.1 issue so I re-installed 1.6.8… still wouldn’t load the LMXShield AND now, 1.6.8 can’t “see” the COM ports. So, any “fresh” advice on how to get the IDE to recognize them would be greatly appreciated? (have attached screen shot of Device Mgr if this helps)!