I guess that Mendeley doesn't know how to fix the issue that you and several other users are experiencing, including me. I'm very disappointed and now I'm looking to other reference manager to migrate my library.
The cause may be the failure of local database. I faced with same error and solved it with the method below. Please try it at your own risk.
1. Delete Mendeley Desktop from your Application folder.
2. Delete two folders: /Users/username/Library/Application Support/Mendeley Desktop and /Users/username/Library/Application Support/Mendeley Ltd.
3. Reinstall Mendeley Desktop to Application folder.
4. Open Mendeley Desktop and log in to your Mendeley account.
When logging in, you may find the message that the local database is crashed. In this case, I assume you have to delete your local database and resync it with the database on Mendeley's server.
After the resync, Mendely Desktop is finally working on my Mac.
I am sorry to hear my solution does not work well.
I guess there are some data or "garbages" remained in your Mac even after Mendeley uninstallation and my procedure.
Maybe you can search other folders related to Mendeley, delete them, and reinstall Mendeley. Of course, please be careful not to delete your important data.
During several years I used Mendeley on MacOSX but, it's was impossible keep Mendeley working properly... tooo much bugs. I spent ten's of hours trying to make it work correctly. I gave up to try any solution!!! I move to Bookends where you can manage thousand's of references easily, it stores your paper's on webdave and the most important, it's very, very, very, stable. It's not freeware but the time you save worth the money.
Good afternoon Adrián Segura Robles , thanks for your indication but I prefer to work with the bibliographic manager Mendeley, I find it more complete, with more analysis options. It is true that I have worked much more with this manager, so my answer is totally subjective ;-D.
I will take your suggestion and learn more about Zotero to enable me to compare them.
Any one has any recommended reference mangers other than Mendeley for Mac? It's been a headache for me lately with Word on Mac. Tried Zotero, still a pain with no easy search citation option. I appreciate your recommendations. Thanks!
My Mac is currently running Catalina it would not let my Mendeley Desktop run so I removed the desktop. I added Mendeley Cite to my Microsoft Word (not 365, but it should work with 365, too) and I access my Mendeley Account online and I can add the citation for whatever article is listed in my library. With Word accessing my online Mendeley library there is no need for the desktop. Yeah!! I want to update my iMac to the Big Sur but I had issue with it the first time. Trying it on my MacBook tonight. Dr. Mj
I am using Big Sur 11.4 and followed partially what Elli Diakanastasi shared before.
So, I uninstalled the previous Mendeley app that would not open, empty the trash bin. Only then, using SAFARI, download Mendeley from here: https://www.mendeley.com/autoupdates/installers/1.19.4
It opened without problems, logged in, and accepted the suggested update to 1.19.8. It worked perfectly. :)