Chosen Solution
Since upgrading my 2012 unibody MBP to Mojave, network preferences will not save or automatically join networks. Whenever the computer is restarted or wakes up my wifi network must be manually joined. I have 2 networks which use different routers but the behavior is the same for both. I did not have this problem before upgrading to Mojave. I have tried creating a new wifi network but the problem persists. Any ideas on how to fix this? Thanks.
Very odd! First make a full backup of you drive! If you haven’t already make a USB OS installer following this guide: How to create a bootable macOS Mojave installer drive You’ll need to run Disk Utility from the OS installer did you get any errors? If you did let us know what you got. Update (05/27/2019) Then I think you need to replace your HD SATA cable. As one of the issues with upgrading in this series is the original drive was a SATA II (3.0 Gb/s) drive and the original SATA cable was only rated for SATA II. So when you put in the SATA III (6.0 Gb/s) SSD (which is a good thing!) You forgot to replace the SATA cable with the newer SATA III (6.0 Gb/s) rated version! Here’s the needed cable MacBook Pro 15" Unibody (Mid 2012) Hard Drive Cable and here’s the iFixit guide MacBook Pro 15" Unibody Mid 2012 Hard Drive/IR Sensor Cable Replacement. There are two additional things you need to do one is placing a stripe of electricians tape on the uppercase when’re the cable crosses over as the rough surface of the aluminum wears the cable. In addition, you want to roll the bends not fold them! Basically I take the ink straw from a Bic ballpoint pen and use it to help be shape the radius of the bend. If you don’t have a pen a bamboo skewer will also work.
