uodated to 10.5.1 now logic won’t start

I've moved all of my plug-ins and related files to an external drive. I then removed my Logic 10.5 application and went and downloaded it again, although it automatically downloaded 10.5.1 installer because I wasn't given a choice. Of course, that download included all of the necessary files for the basic installation. This took about an hour. This was last night. I activated the program and saw the same "Updating information about audio unit plug-ins", which is what I saw before I did all of this and my plug-ins were all intact. I was temporarily encouraged when I read someone in this thread explaining that it took him a long time but that his patience eventually led to success. I decided to go to bed and check things out when I got up this morning. This ran and remained in that cycle from 11:00 last night until this morning at 7:00 when I finally decided to interrupt the loop, at which time I was "Logic Pro X not responding". So I have no remaining plug ins to check and it wasn't checking anything anyway because it became immediately unresponsive! I'm glad that the project that I wanted to finish this weekend was only for myself and I wasn't doing any of this for a client! I'm hoping that the official support people pay attention to this problem and feel pressured enough to solve it! I have no other recourse that I can see!!!

Possible Workaround that worked for me.

I moved everything out of my Hard Drive - Library - Audio - Plug-Ins Folder and saved it somewhere else. Logic 10.5.1 started immediately, no audio unit scan. smdh. I have no audio units in my User Folder - So this worked for me.

Gonna put back the components now and see if it still works - *Fingers crossed*

Seems like DUY plugins are the culprit, i've gotten errors with them before because sometimes you don't see the little "OK" button to click to proceed on a big screen . I removed them and logic starts fine. Also the Loudness Penalty plugin crashes 10.5.1.

I think that I possibly did not remove enough. I had plug-ins from Kontakt, Izotope, and PianoTeq. I only removed the portion that seemed to be embedded in my Logic files. So I have now removed all of those separately, just for existing on my drive, having nothing to do with Logic. Again, I removed my main Logic Application and I feel that I have gotten rid of anything on my computer that could be incorporated into Logic later. I went back and downloaded Logic and I’m just now running it and I see no change, as it still seems to be in the endless loop of letting me know that it is updating the audio unit plug-in information. I’m willing to wait for an hour or two but I’m afraid that if this continues until I’m ready to go to bed, which will be in six or seven hours, then I really don’t have any other ideas?

it popped up for me immediately , no waiting. Maybe you're not removing enough. I cleared out my components folder completely first, then added by First letter , batch by batch til i found the culprit.

I am using a 2016 MacBook Pro. I have made sure to do all of the maintenance and malware removal and keep everything updated. My solution is the ultimate “overkill“ and I’ve needed to do this for a while and I felt that now was finally the time. I am doing a clean install, which should remove everything, including things that I probably wish I could have left alone but at least everything has been backed up and I will have to reinstall everything one by one that I feel I still need. This will be quite an evening but at least I should be able to wake up to the ability to once again use Logic Pro X the way that I always have since I first purchased it several years ago and it has managed to operate continuously since then with no problems until yesterday! This way I will not have lost my entire weekend and I will still have one day to make progress before Monday!

Good luck. For what it’s worth, someone on the Logic Users Group forum suggested that those of us experiencing these issues probably have computers on the fringe requirements for this latest version of Logic (under Mojave.)

Apple clearly wants every user up to date w current hardware and software even though it is unrealistic.

so, it might make sense for us to hang around 10.5.0 unless we are willing to jump up to the later OS.

there might be something to that.

If I hadn’t had everything working perfectly with Logic 10.5 then I might agree that it’s possible that my system is too old, but with four years of perfect operation and then everything crashing with a one decimal point upgrade it’s difficult to believe that my four year old MacBook Pro is suddenly insufficient. I am still going through the long arduous process of completely starting from the ground up with the re-installation of Catalina, followed by the meticulous installation of each application that I had removed. It seems like it should work, but I’m also suspicious that I shouldn’t have had to go through all of this, that I have never had a previous problem.

Updating from Logic 10.5 to 10.5.1 has caused what looks to be serious loading issues having to do with plug-ins as others have reported. I first got an alert box saying the Garritan Aria player and the Garritan CFX Concert Grand player have issues and they produced no sound. I did find an Aria Engine update from 6/12/20 that I installed. I did get sound from the CFX Concert Grand after that install but not the Aria Player. I also saw a yellow ( !) alert in the plug-in load button for Aria. Then Logic 10.5.1 started stalling with the endless beach ball while saying it was checking the plug-ins. I tried removing those Garritan plug-in components from the Components Folder but Logic 10.5.1 still stalled. Now Logic 10.5.1 won't even get as far as checking the plug-ins unless I do a restart after the beach ball stall. . I have also tried resetting the NVRAM and SMC. 2009 5,1 Mac Pro. Mojave 10.4.6. I have never had an issue like this with Logic Pro X since purchasing it in 2014. I also have a copy of Logic 10.4.8 that does work without issue.

Ok, I found a way to finally open Logic 10.5.1. If you move all the .components to another folder, so that it there are no more .components in the 'Components' folder, then Logic should open. You don't have access to your 3rd party plugins, but that's the compromise right now, until Apple fixes this.

I use very few of the Logic plug-ins but one could possibly use them and then swap them out for the third party ones later. As I stated, I do still have Logic 10.4.8 working, hopefully. So that should work best for me as I won’t be using the new tools added In 10.5 except for maybe the samplers.

I had the similar issues...

This worked for me:

I deleted the Audio Units Cache:

https://www.youtube.com/watch?v=DTtK6oIk5vk

Then I did a rescan. I still had some popup windows with error messages of pug-ins which wouldn't load. Each time I clicked "cancel", they came up again.

Then I went to Preferences-> Security -> General.

There I could allow each Plug-In with Error Messages to load and then Logic would start again.

Maybe it helps for you as well...good luck!

I finally got things running last night but it was only by totally doing a clean install, and then reinstalling things that I had removed in order to do this. Everything works fine again now but unfortunately the weekend is gone!

I’m back on Logic 10.5.1. I also deleted the AU Cache and I also deleted the com.apple.logic10.plist file in the Go/Library/Preferences Folder.

I tossed the AU components that I knew were old junk (even an old VST) and then copied many of the rest of them to a desktop folder before sending them to the trash. Eventually Logic made it through the plug-in scan.

Until version 10.5.1, I have never had a problem with previous upgrades. After two days of despair and failure to succeed with anything I tried or could think of, I went the route of potential “overkill“ and I found a solution that’s guaranteed to work for anyone with the same problem. A fresh brand new clean install! Ahead of me now will be an equal amount of time spent reinstalling everything that I had removed by doing this!