Thunderbolt 3 Ports Stopped Working After Ram Hard Drive Upgrade Imac Intel 21 5 Retina 4K Display 2017

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After doing the upgrade my thunderbolt 3 ports stopped working. All other ports are working fine. Anyone know of any solutions?

The same exact thing happened to me tonight. All aspects of my 2017 21.5 iMac are working fine, but my external monitor is no longer being recognized. No one seems to have a good answer for this, but resetting SMC or NVRAM do not seem to work at all.

Guess I just have to hook up my monitor on the USB 3.0 port.

Hi,Did you ever get your ports working again?I just did the ram on mine and thunderbolt no longer works for my display.