0

I have a Mac Pro 5.1 (2010) with 3 HDDs installed.

One is a 1 TB running Snow Leopard. Another one with 2 TB for file storage and a third one I have added recently (WD Gold 4 TB).

I have tried to upgrade my OS to High Sierra, but firstly the new HDD didnt show up. Later on when I managed to get it displayed, I formatted it with Mac OS Extended (Journaled) and GUID Partition Table. I ended up with 2 Partitions. 1 TB for the OS and 3 TB for Files.

After the successful Installation, I booted up and a Prohibited Symbol popped up. I restarted and held down the alt key to select the same partition again.

Long story short. Every time I boot up the symbol pops up once and after a reboot, I can use the OS. The same process over and over again. Keeps repeating. One time it works, then not, then it works again.

I have downloaded the High Sierra installer and used the (Install Disk Creator) provided by MacDaddy.io

Everything works like a charm as soon I boot in, but it is really annoying that the first boot always get blocked with the prohibited symbol.

What is causing this weird issue?

*I already tried reinstalling OS in SafeMode.

Your Answer

By clicking "Post Your Answer", you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.