Mac error code 36: What it means and how to fix it quickly

Keep coming face-to-face with error code 36 on Mac? It's a frustrating one. I've run into this on my Mac running macOS Tahoe while copying folders to an external SSD and even between two local folders. The good news is, it's usually a simple file read or write hiccup, not a dying Mac. So let me walk you through how to resolve it quickly.

What is error code -36? (Why it happens)

Error -36 basically means the Finder couldn't read or write file data properly. In practice, it often appears when hidden metadata files like .DS_Store or other dotfiles in a folder are corrupted. Root causes I see most:

• A damaged file

• Wrong permissions

• A cranky external drive

• Recent software glitches.

It's not dangerous if you handle it carefully, and in most cases, it's fixable within minutes.

Quick housekeeping before you dig further into fixes

Use CleanMyMac to clear safe caches and temporary junk. That doesn't fix files, but it removes noisy clutter that can trigger file-operation errors and gives Finder a clean slate to test again; here's how:

1. Open CleanMyMac — get your free trial here (seven days).

2. Select Smart Care > Scan.

3. Run tasks.

What is error code 36 on Mac: Quick diagnostics (is it software or hardware?)

Ok, time to run some quick diagnostics, work through this list.

1. External drive sanity check

Eject the drive, unplug, restart the Mac, then reconnect. Try the copy again.

2. Scope the issue

Does -36 error happen with one file or everything in that folder? Narrow the culprit by copying smaller sets.

3. Relaunch the Finder

1. Apple menu > Force Quit > Finder > Relaunch.

4. Check "Locked"

1. Select the file or folder.

2. Click File > Get Info.

3. If Locked is checked, uncheck it and retry.

5. Update macOS

Install the latest point release. I've seen the Mac error code 36 disappear after an update.

5 manual fixes (in order of difficulty)

1. Use dot_clean to merge broken dotfiles

On your Mac, dot_clean tells macOS to reconcile the messy resource forks and dotfiles that often cause -36.

1. Open Terminal.

2. Type: dot_clean 

3. Drag the problematic folder into Terminal to paste its path.

4. Press Return, then try the copy again.

2. Correct permissions

1. Select the file/folder > Get Info > Sharing & Permissions.

2. Make sure your user is Read & Write.

3. Click the lock to authenticate if you need to change it.

4. Use the gear menu > Apply to enclosed items… for whole folders.

3. Run Disk Utility First Aid

1. Open Disk Utility (Applications > Utilities).

2. Select the external drive (or your volume) > First Aid > Run.

3. This catches directory damage that can trip Finder.

4. Delete bad .DS_Store files (scoped, not system-wide)

If a folder's metadata file is corrupt, remove it safely.

1. In Terminal run:
   
   sudo find <paste_affected_folder_path_here> -name ".DS_Store" -depth -exec rm {} \;
   

2. Enter your password, press Return, then retry the copy.

Tip: Don't run this across your entire disk. Keep it to the affected folder or the external volume.

5. Update macOS and retry

If you skipped this tip from earlier, make sure you do this now. This can really instantly fix the issue. System Settings > General > Software Update.

6. Reset Finder

Use Applications > Uninstaller from CleanMyMac to reset Finder and remove any corrupt files that may cause the error. Here's what to do: 

1. Open CleanMyMac and click Applications > Scan > Manage My Applications. 

2. Click an arrow (>) next to Finder and select everything except binaries. 

3. Hit Remove. 

This way, you can reset any misbehaving app, including preinstalled ones. Cannot see them in the list? Go to CleanMyMac Settings > Ignore List > Uninstaller and deselect the checkbox next to Ignore System Applications.

Also, you can check for third-party add-ons that hook into Finder's file operations. Things like cloud sync clients, archivers, duplicate finders, or apps you don't use. Just use the Leftovers tool and remove remnants.

Automatic tools vs manual fixes

When it comes to knowing how to fix Mac error code -36, what is the best method? The manual fixes or the automatic sweep. Well, here's my take.

• Rule of thumb: Urgent deadline = automatic first, learning and prevention = manual sequence

If you want speed and fewer mistakes, run an automatic sweep first: open CleanMyMac > Smart Care > Scan to clear caches and temp junk that can trip file operations, then within the same app run Protection > Scan to rule out adware or odd launch agents.

Preventing future Mac Finder error code 36

• Keep macOS updated.

• Eject drives properly.

• Light maintenance, a monthly Smart Care in CleanMyMac clears caches and leftover junk that can poison file operations.

• Watch free space and health.

• Buy decent storage.

When it's time to seek professional help

• You've tried all fixes in this article.

• Disk Utility First Aid repeatedly reports errors that return.

• The external drive clicks or disconnects under load.

• The error appears across several devices (Macs and drives), hinting at a deeper controller or cable issue.

At that point, weigh the cost: Apple Store or an Authorized Service Provider for Mac. If replacement is cheaper than recovery, clone what you can and move on.

So, we've covered everything on Mac Finder error code -36.