3 Proven Fixes for AppleScript 'do script' Error (2025)

Pro Tip: If a script is still failing after you've checked these settings, try toggling the permission off and then on again. This can sometimes force the system to re-register the setting.

Fix 2: Decoding Cryptic Errors with the Script Editor

Sometimes, the problem isn't permissions; it's the code itself. AppleScript error messages can be notoriously unhelpful, like "Can't get item 1 of {}." What does that even mean? The key is to learn how to use the built-in debugging tools in the Script Editor.

Mastering the Log Pane

At the bottom of the Script Editor window is a small pane that is often overlooked. It has tabs for Result, Messages, and Events. This is your command center for debugging.

• Result: Shows the final output of the last command that was successfully executed. If your script stops, the last result can give you a clue about where things went wrong.
• Events: Shows every single command your script sends to an application and the reply it gets back. It's verbose, but incredibly useful for seeing the exact point of failure.
• Messages: This is where both errors and your own custom log messages appear.

You can add your own debugging lines to your script using the log command. This is invaluable for checking the value of a variable at a certain point in your script.

tell application "Finder"
  set the_files to every file of the front window
  log "Number of files found: " & (count of the_files)
  
  repeat with a_file in the_files
    log "Processing file: " & (name of a_file as text)
    -- your other code here
  end repeat
end tell

By running this script and checking the "Messages" tab, you can confirm if your script is correctly identifying the files you expect it to.

Using 'Try' Blocks for Graceful Failure

A great way to pinpoint errors is to wrap questionable code in a try...end try block. This allows you to "catch" an error and display a more helpful message instead of having the script just crash.

try
  tell application "NonExistentApp"
    -- this line will fail
    activate
  end tell
on error errorMessage number errorNumber
  display dialog "An error occurred!" & return & return & ¬
  "Message: " & errorMessage & return & ¬
  "Error Number: " & errorNumber
end try

This will produce a clean dialog box with the specific error message, which is far more useful than the generic script error.

Fix 3: Speaking the Right Application Language

A script can have perfect syntax and all the right permissions but still fail if it's giving the wrong commands. Every scriptable application has a unique "dictionary"—its own set of commands, objects, and properties that it understands. If you use the wrong term, the app won't know what you mean.

How to Read an Application Dictionary

In Script Editor, you can view any app's dictionary by going to File > Open Dictionary... and selecting the application. This is your instruction manual.

For example, if you open the dictionary for Finder, you'll see you can get the name, size, and kind of a file. But if you try to get the subject of a file, it will fail, because subject is a property of a message in the Mail app, not a file in Finder.

Targeting the Right Element: Specificity is Key

A common mistake is being too vague. You can't just say "get the name of the file"; you have to specify which file. AppleScript works on a hierarchy of objects.

Here’s a comparison of vague vs. specific commands:

Incorrect (Vague)	Correct (Specific)	Why it Works
tell app "Finder" to get name of file	tell app "Finder" to get name of file 1 of the front window	Specifies exactly which file you're targeting.
tell app "TextEdit" to set font to "Helvetica"	tell app "TextEdit" to set the font of paragraph 1 of document 1 to "Helvetica"	Targets the specific paragraph within a specific document.
tell app "Mail" to get sender	tell app "Mail" to get sender of message 1 of the inbox	Drills down through the object hierarchy to the specific message.

When in doubt, consult the dictionary and be as specific as possible in your commands. Use the Event Log (as mentioned in Fix #2) to see exactly how your script is trying to target an object.

Putting It All Together

AppleScript can feel like a dark art, but it's usually governed by logic. When your script inevitably breaks, don't despair. Run through this checklist:

1. Permissions: Is my script runner (Script Editor, etc.) allowed to control other apps and access files under System Settings > Privacy & Security?
2. Debugging: What are the Log Pane and Event Log telling me? Can I use log statements or a try block to isolate the problem?
3. Dictionaries: Am I using the correct commands and properties for the target application? Am I being specific enough in my targeting?

By approaching the problem methodically, you can solve over 90% of common AppleScript issues. The power to automate your Mac is well worth the effort of learning its language and rules. Now go fix that script!