I have a 2015 iMac 21.5" that has slowly ground down to crawl. I had this great idea of installing macos on an external SSD (Kingston 2TB) and run it from there instead but no matter what I try I can't get it to work.
At first I downloaded the installer for Monterey but the HDD isn't great and it kept crashing and restarting partway through.
Then I tried installing to the SSD from Recovery (internet recovery wouldn't get past wifi choice so had to use non-internet) but even though the installation went ok it continued to boot from the HDD and in Startup Disk the SSD wouldn't show at all.
Then I made a USB boot stick and did the same steps above with the same result.
The SSD has GUID map and I tried both Mac OS and APFS formatted.
Does anyone have an idea what might be going wrong? Thanks in advance!
The last episode of Enterprise is the one before that. There is no Riker's holodeck!