iMac Constantly Crashing

Sorry you are having this problem. The very best way to determine what is going on is for you to download, install and run the free app EtreCheck. Be sure to enable full disk access. Save the report and then post it below under "Additional text". It provides a complete picture of what you have installed, plus other information which can point to the issue. Then I am sure that someone here will offer some useful suggestions. In the meantime I would ty a restart in the Safe Mode. Be patient as it can take up to ten minutes. This enables the computer to do a lot of repairs and cache cleaning and might even solve your problem. Then restart normally. Let us know how it goes.

You can save you and us a lot of time and effort if you do the following:

Please navigate to the Mac App Store or navigate to www.Etrecheck.com and download the free version of EtreCheck. Once you have you downloaded the app and installed it, please run the report and save it. This report will help us get a good idea what has been installed on your system and help us be able to diagnose what may be wrong.

When you have your report, you can attach it when you reply to this message and we can then review it and help you determine what is needed to get your system running well again. 

For instructions on how to download your EtreCheck report and attach it to your reply to this message please click https://discussions.apple.com/docs/DOC-250000211

The best antivirus, cleaning app, and overall maintenance app for Mac OS is Mac OS itself. All you need to do with Mac OS to keep it secure and running well is to keep it up-to-date and do periodic (about 1x per week) restarts. Other than that, leave it alone. Adding third party antivirus, cleaning, security and other types of maintenance apps to Mac OS adds no additional level of security. The only thing these apps do is have the opposite affect users want. They make Mac OS slow, unstable, generate odd behavior (much like you are experiencing) and make Mac OS appear buggy. 

Please locate the developers uninstall instructions for Bitdefender & Antivirus One and follow to the letter. Then restart in Safe Mode per the directions in Use safe mode to isolate issues with your Mac and then restart normally. 

One you have done that please download FindAnyFile and search the system for anything with

• Bitdefender
• Antivirus One

in it, move to Trash and please empty the Trash.