Odd Bootup Behavior

I just had the same problem with my installation as well. Macbook Pro mid-2012. I updated Mojave from High Sierra. After installation, the computer has started again on the login screen. I typed the normal password, the the bar moves until the middle, then black screen for some seconds, and it gets into the desktop. I supposed it was a problem because I am using a pre-retina computer, but it is not that the issue.

As nmeed above, may I ask for a possible the solution for it? SMC does not help. the pattern also happens in Safe mode, which is also slow to start anyway. Having visual problems, the dark mode helps, but the slow start is something bothering me of course.

 

I think I might have the same issue, except mine also shows the Apple logo above a progress bar for a few seconds after logging in. i.e. enter password and log in and it shows the progress bar as usual, then the screen goes black and it shows a white Apple logo and white progress bar few a few seconds, then the desktop appears.

It seems like this thread is describing the same issue:

https://discussions.apple.com/thread/8552067

I did a reinstall of Mojave and restored a Time Machine backup and the same behaviour remains.

 

I have just finished updating a late 2013 iMac with Fusion drive and two MBPro laptops both early 2015 without problem, however, I also have the above issue.

 

i think this is a bug. i did a clean install of mojave and have this behavior.

 

+1 I got the above as well

 

I've got the same issue. Mojave clean install (15" MacBook Pro 2014)
Edit: Filevault is off

 

Based on your description of the problem, it sounds like you have FileVault turned on?

 

For me, it is as following: it lights up with boot chime, Apple logo and progress bar, as normal. Then, there is brief black screen for few seconds, then it shows the screen with progress bar almost finished for a few seconds, and that is it!

So, you can say that only difference from HS for me is a brief black screen. Does not bother me.

 

+ 1 same issue with me

 

If you have File Vault enabled the first part of boot is accessing and unlocking the drive.

If you have a T1 or T2 chip, the bridge OS boots before macOS.

 

Except this happens even when FileVault isn't enabled, and it didn't happen in High Sierra, and after logging in it now has an extra step that dumps you back to a black screen with the Apple logo and a progress bar.

 

I don't have File Vault enabled and my 2012 MBP does the same; doesn't really bother me, though.

 

i wonder if this is fixed in the 10.14.1 beta?

i wont be able to find out till public release of that version. not using a beta.

 

OP wrote:
"I updated to Mojave yesterday and I noticed that during bootup, the screen goes blank midway, then a while later, the progress bar shows back up and then I enter my desktop."

I've seen similar behavior here (2012 Mac Mini), but I've come to the conclusion that the "momentary blacking out" has something to do with the graphics loading/initializing.

I notice this almost every time I "switch boot" back-and-forth between my regular working OS (Low Sierra) and High Sierra or the new Mojave.

It always "comes back", so I accept it as something to do with the peculiarities of how the graphics load up, and don't worry about it.

Have you tried a couple of power-downs/reboots to see if it persists?

 

Same here...
But the total boot-up time has increased drastically...
Before...on Yosemite...the Mac (late 2013 was up and ready to go at the exact same time the HD in the Time Capsule
stops spinning...Now there's an additional +/- 40 seconds...

 

I got this tip from another post:

I found of going to preferences, unlocking, reassigning the hd as startup, and restarting solved the slow boot problem for me.

 

I think, what he means is go to system preferences, startup disk, unlock it by entering your password, then click on your Macintosh HD and then click reboot.

I have no idea why, but this solved the slow boot up issue for me, too.
Even though the black screen with the white Apple logo and the white status bar still appears.
Filve Vault enabled on my system.

 

Same here - encrypted APFS startup partition. I’m asked to type in my password then the progress bar moves, black screen comes and covers the entire screen for like 2 seconds, then I’m at my desktop. rMBP 2015. Definitely an OS system-wide bug, seeing that many others are having this same issue.

Edit: didn’t pay attention thoroughly. Just did again, and it’s actually about 5 seconds of blackout, then the apple logo and progress bar again, for about 2 seconds, then the desktop. Annoying bug.

 

Things got fixed in 10.14.1 PB1 (18b45d).
Everything works as expected with FileVault off.
With FileVault on, however, you will always get the default Mojave picture as login background other than the picture that was set as your desktop. Hope that they can fix that as well.

 

Same issue here

 

Same issue here on my 2018 6-core Macbook Pro.