Finder error -36 when reading or writing data on MacBook Pro

CPW wrote:

Error code -36

This indicates an "I/O Error" which is generally due to a hardware issue.

It does appear that my hard drive is out of memory.

FYI, memory & storage are two completely different things. Hard Drives, SSDs, USB sticks, SD Cards are all storage devices.

https://www.corsair.com/us/en/explorer/diy-builder/memory/whats-the-difference-between-memory-ram-and-storage/

I've tried to offload things like photos and music files as well as old files to free up space. Under Info for the machine itself, it says Size: 1 TB used (429 GB on disk) for about 91 thousand items.

The only important and accurate storage value is the Free storage space value which unfortunately is only shown in Disk Utility or the System Profiler. Ignore the "Available" storage value shown everywhere within macOS since it is very misleading and is not synonymous with Free. Even the "Used" storage value can be misleading.

And the different categories listed in Storage Management may not indicate what you think they do. Those categories are based on file types not locations on the drive. For example "Applications" will mean the items stored in the "/Applications" folder, but may also include any type of executable app found anywhere else on the drive....even in the Downloads folder.

It's giving me "The operation can’t be completed because an unexpected error occurred (error code -8062)." (Is there such a thing as an expected error?)

Unfortunately yes.....most of Apple's error messages are very cryptic.

I'm running a scan using the Clean my Mac app and it has been running for 12 hours or more, although there's on indication that it is actually running.

Uninstall CMM by following the developer's instructions & hope it is completely removed. CMM has a notorious reputation on this forum for causing all sorts of problems. Also avoid any other anti-virus software, cleaning/optimizer apps, and third party security software because none of them are needed & they all usually cause more problems than they solve because they interfere with the normal operation of macOS.

It says there is a Software Update available (Sequoia 15.7.3) but it's unable to download it and displays a message More Storage Required.

That is very bad because it means you are running out of Free storage space. People need to always have at least 20% of Free storage space at all times.....more may be necessary depending on your workloads. Once Free space goes below 20GB, that space can disappear very quickly even for light workloads. When you completely run out of Free storage space, then bad things will happen such as not being able to delete any files to make more room due to how the APFS file system works.

Run the third party app EtreCheck and post the complete report here so we can examine it for possible clues.

How to use the Add Text Feature When Posting an EtreCheck Report - Apple Community

I also started backing up a lot of folders to a new 1TB disk. I'm using 11GB on that disk. Oddly it says Capacity is 4 TB for that drive. I formatted it to APFS.

Did you use Disk Utility to erase the whole physical drive before you started using it? See this older version of the Apple article from the Internet Archive:

https://web.archive.org/web/20250909095655/https://support.apple.com/guide/disk-utility/erase-and-reformat-a-storage-device-dskutl14079/mac

What file system is on this external drive?

FYI, these days there are a lot disreputable sellers who are selling counterfeit drives online through the common market place vendors. It can be very difficult identifying fake & real drives these days as the scammers have gotten more sophisticated in hiding their fakes from easy detection.

Make sure this external drive is connected when you run the EtreCheck report so we can get some details about its purported model information.

CPW wrote:

It does appear that my hard drive is out of memory. I've tried to offload things like photos and music files as well as old files to free up space. Under Info for the machine itself, it says Size: 1 TB used (429 GB on disk) for about 91 thousand items.

Under Storage it says Applications are consuming 408.91GB on the disk. It's calculating a value for Photos and System Data and I think has been doing that all night.

It says there is a Software Update available (Sequoia 15.7.3) but it's unable to download it and displays a message More Storage Required.

ICloudDrive Info says 417.2GB (18.42 GB on disk) and that Syncing has been disabled due to insufficient disk space. I seem to be stuck. I have rebooted several times. I also removed most of my TimeMachine drives.

I also started backing up a lot of folders to a new 1TB disk. I'm using 11GB on that disk. Oddly it says Capacity is 4 TB for that drive. I formatted it to APFS.

It's giving me "The operation can’t be completed because an unexpected error occurred (error code -8062)." (Is there such a thing as an expected error?)

I'm running a scan using the Clean my Mac app and it has been running for 12 hours or more, although there's on indication that it is actually running.

Any other suggestions? Seems like I need to safely offload more files to my new 1TB disk.

Start by uninstalling Clean My Mac per the guidance found at the developer's website. https://macpaw.com/support/cleanmymac/knowledgebase/uninstall-cleanmymac

The app is unnecessary and does nothing the macOS cannot do for itself, except conflict and cause problems.

Then keep chipping away at the files you have stored on the startup drive. You want/need to keep a minimum of 100-150 GB free at all time to let the OS run properly. If you can't move large files and folders, move smaller ones first to your et drive and then delete them from your Mac and empty the trash. You might want to startup in safe mode to do this.

CPW wrote:

I'm running a scan using the Clean my Mac app and it has been running for 12 hours or more, although there's on indication that it is actually running.

Do NOT use CleanMyMac. There is a reason why it is referred to as BrickMyMac and it should be uninstalled using their uninstaller to make sure all fragment processes are removed. You can use the Search option on the top of the screen here and enter CleanMyMac where you will find users who had their machine trashed with the only recourse being a Factory Reset.

What do you mean by removing most of your Time Machine drives? Is you manually attempted to delete snaphots by dragging them to the trash or using a cleaner to do that, it can lock the files in your Trash and prevent them from being removed. There is a method to remove local snapshots and it is done by following the steps here:

About Time Machine local snapshots - Apple Support

I would recommend starting up in Safe Mode and removing unused Applications and Documents files there. Starting up in Safe Mode will be slow and take much longer to start than usual and once you are done, it can be exited by restarting again.

Start up your Mac in safe mode - Apple Support

After CleanMyMac has been removed and you have started up in Safe Mode and removed the unused files to clear as much as space as possible, then post the screenshot of  > System Settings > Storage. It may take some time to calculate Photos and System Data, but certainly not all night.

Is there some reason why your iCloud Drive storage is so huge? The files there will attempt to save them on your Mac when possible for offline use and automatically offload when storage is contained. Is there some thinning that can be done there? Moving files from your desktop to iCloud Drive does not automatically free up space on your computer. iCloud is a syncing service to make access to files seamless across devices, it is not an external storage solution.

And then finally if you are able to download the free EtreCheck app, post the report using the Additional Text option when posting. The report contains no personal information. It is also a lightweight program that will not clog your computer by consuming the limited storage resources.

How to use the Add Text Feature When Post… - Apple Community

I don't know if this is still the case – but the Finder used to have problems with copying very large numbers of files. The symptom was that it would put up an "Error -36" mid-way through the copying operation.

A workaround for that was to use a backup application like Carbon Copy Cloner or SuperDuper! to do the copying.

CPW wrote:

I'm running a scan using the Clean my Mac app and it has been running for 12 hours or more, although there's on indication that it is actually running.

Any other suggestions? Seems like I need to safely offload more files to my new 1TB disk.

There are two very different schools of though for treating CleanMyMac aka " BrickMyMac"

The steps in #1 below is predicated on the Offending  Application has been Removed as per the Developers Specific Instruction 

#1 Some Contributors suggest restarting in Recovery Mode and choosing to Reinstall the Operating System over the existing installation. 

This may or may not replace elements of the  Home Folder ( User Account )  and replace any corrupted or removed elements and make things right.

#2 - Then there are Other Contributors ( like myself ) would suggest  from this link Use Disk Utility to erase a Mac with Apple silicon.

For Intel computer >> Use Disk Utility to erase an Intel-based Mac followed by How to reinstall macOS

Thereafter to start from scratch and install all Required Applications directly from the Apple Apps Store or Directly from the Developer.

 We are happy to help you but you're going to have to give us something more to work with. Details matter.

Please see: Writing an effective Apple Support Communities question - Apple Community

CPW wrote:

I ran the Etre Report but I have to pay for it to share it. I recognize the unsigned apps except for something called iStumbler.app which is a "utility for finding wireless networks and devices". I sort of doubt that is causing the memory issues.

You do not need to pay for EtreCheck in order to post the report here. This app was developed by a respected forum contributor for the purpose of posting here on this forum so other contributors can analyze the report to assist people. Check out the link I provided which contains instructions for capturing & posting an EtreCheck report on this forum. Even the EtreCheck app has instructions on how to post the report here, but I'm not sure how to access those in app instructions.