Finder is running really slowly

AndrewTandem wrote:

... Other computers (purchased at the same time) in my office have the same software and are running Sophos too but their machines are running fine.

Have they also been affected by "CleanMyMac"?

Excerpted from Effective defenses against malware and other threats:

• Never install any product that claims to "clean up", "speed up", "optimize", "boost" or "accelerate" your Mac; to "wash" it, "tune" it, or to make it "shiny". Those claims are absurd.
  • Such products are very aggressively marketed. They are all scams.
  • They generally operate on the flawed premise that a Mac accumulates "junk" that needs to be routinely "cleaned out" for optimum performance.
  • Trial versions of those programs are successful because they provide the instant gratification of greater free disk space.
  • That increased space is the result of irreversible destruction of files, programs, or operating system components normally protected from inadvertent alteration or deletion. The eventual result will be unreliable operation, poor performance and random crashes that may not become evident for months or even years after their use, when updates to programs or macOS are eventually released.
  • Memory "cleaners" that circumvent a Mac's memory management algorithms work by purging inactive memory contents to mass storage, which can only result in degraded performance and accelerated hardware failure.

Merely uninstalling ill-conceived "cleaning" apps, even when performed in strict accordance with their instructions (which often don't work) is usually an insufficient remedy due to the effects of having used them. Very briefly stated, the recovery procedure from having used such things is as follows, and in the following order:

1. Back up the Mac using Time Machine or an equivalent backup strategy
2. Remove the scam "cleaning" products according to their instructions, and evaluate
3. Reinstall macOS using macOS Recovery, and evaluate
4. Reinstall all other potentially affected apps, and evaluate
5. Erase the Mac completely, followed by reinstalling macOS, followed by reinstalling essential apps from their original sources, followed by migrating User content from the Time Machine backup.

Since the results of Steps 2-4 are almost always unsatisfactory, I omit them as unnecessarily time-consuming.

An expanded procedure for Step 5 is provided in the reply that follows this one. Be sure to read everything and understand its implications. Less drastic solutions certainly exist, but this one will probably result in the least amount of your time and need for constant interaction. It is also unequivocally supported by Apple's published documentation, is what a Genius Bar would do if you were to pay them to do it, and it is the exact same procedure I use given a Mac that has been affected by similarly categorized products.

It is not reasonable to expect a Mac to operate normally after using "CleanMyMac". Like many ill-conceived "cleaning" utilities, it is capable of corrupting a Mac to the point that erasing it completely is the only practicable means of recovery. "CleanMyMac" is not the only example; it is merely popular due to marketing strategies that are as effective as they are intrusive.

There is no practicable way to reverse the effects of having used those products other than to reinstall all affected files from backups or their original sources. Reinstalling macOS alone will have no effect on either removing "CleanMyMac" or reversing the damage it is capable of inflicting upon a system.

To recover from the effects of having used it to modify macOS, the additional software you require and the essential files you need, follow the applicable recovery procedure below:

• If you have a backup that you created prior to using CleanMyMac, now is the time to use it. For Time Machine, boot macOS Recovery. At the macOS Utilities screen, choose Restore from Time Machine Backup. Choose a date preceding the installation of CleanMyMac.
• If you do not have a backup that predates the use of CleanMyMac, create one now. To do that read Use Time Machine to back up or restore your Mac.
  • The recovery procedure will require that you completely erase the Mac using macOS Recovery, and then create a new User Account whose contents will be empty. You will then be able to use Setup Assistant to migrate your essential documents including photos, music, work products and other essential files.
  • To erase and install macOS read How to reinstall macOS from macOS Recovery.
    • Follow the instructions in that document under How to erase a disk for Mac.
    • Then, follow the procedure in Move your content to a new Mac.
    • When asked how you want to transfer your information, select Transfer from a Mac, Time Machine backup, or startup disk.
    • Under Select the Information to Transfer, select only your previous User account and do not select "Applications", "Computer and Network Settings" or "Other files and folders". De-select those choices.
  • Subsequent to using Setup Assistant, you will need to reinstall the essential software you may require, once again remembering to install software only from their original sources, and omitting all non-essential software.
  • "Non-essential software" is a broad category that includes but is not limited to third party "cleaning", "maintenance", and "anti-virus" products.

Please post the EtreCheck output as a "Reply" to this thread

<https://discussions.apple.com/docs/DOC-6174> or <https://etrecheck.com>

Click on the Share icon and select "Copy Report"

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And then Paste the report as a "Reply" to this thread using an "Additional Text" box.

If, AND ONLY IF, you get the error:

    "The message contains invalid characters"

then try posting to PasteBin.com, and give us a PasteBin URL link.

<http://pastebin.com/>

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EtreCheck is a tool that helps Apple Support Community volunteers debug problems without any access to the troubled computers. Debugging problems can be a difficult task even when the machine is in front of you. Attempting it via a discussion forum is extremely difficult. EtreCheck is a great help that regards.

Please determine if the same problems occur in "Safe Mode": Use safe mode to isolate issues with your Mac.

Needless to say, if you are using any non-Apple "anti-virus", "cleaning", or "Internet security" products including "banking security", anything at all in that broad category of utterly useless garbage, don't. A lot of things won't work if you do.

Completely uninstall "cleanmymac". This **** should be considered malware and never let anywhere near a mac.

After uninstalling, you should at the very least try running the 10.13.6 Combo Update.

CMM is known to delete files that are should be present, resulting in unstable systems even after it is uninstalled.

The comprehensive solution for a system that has been compromised by running cmm is to do a backup followed by a clean install, and only migrate the user accounts (not applications, settings or other files).

Uninstall Sophos

As mentioned uninstall CleanMyMac

Re-configure the memory into same-sized banks.

Configuration profiles? That can either be intentional, or it can be an indication of compromise