My iMac (21.5 inch 2017 model, 3.4 GHz) had a fusion drive, and I upgraded the ram to 32 GB and replaced the 1 TB drive with a 500 GB SSD. Using Apple's instructions for fixing a fusion drive (https://support.apple.com/en-us/HT207584), I merged the "blade" drive and the SSD into a new fusion drive. I then restored from a Time-machine backup, and reset the PRAM and SMC.
The USB-C ports did not work with my external display when I used a USB-C to HDMI adapter and cable that had worked before, but when I tried another adapter, the problem was resolved. Both adapters were supposedly exactly same, as I had purchased one for my iMac and one for my laptop (https://www.amazon.ca/ICZI-Aluminum-Thun...), but only one worked. The adapter and cable that you are using to attach to your monitor may be the issue.
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crwdns2944067:03crwdne2944067:0
I'm having the same issue.
It's weird, it was working but not it's not. (I just brought a brand new iMac 21.5")
Also, I brought a USB-C to USB 3.0 multi adaptor, the both worked for 1-2 days then stopped.
I'm still seeking the answer.
crwdns2934271:0crwdnd2934271:0 Paul Fowler crwdne2934271:0
I’m experiencing the same issue. I upgraded my iMac to 32GB of RAM and the USB-C ports stopped working. I use practically every combination of new cables to connect to my dual monitor and no luck. Only to find out that the USB-C ports are not functioning any longer. Also, the RAM that I used was from OWC
I wonder how I can address this issue.
crwdns2934271:0crwdnd2934271:0 nazim.deen crwdne2934271:0
thanks a lot, saved my life! ))
crwdns2934271:0crwdnd2934271:0 Valerii Grizodubov crwdne2934271:0