When you reset preferences, the previous preferences file is saved as Adobe Illustrator Prefs.err.
Learn how to fix preferences file issues in Illustrator.
If Illustrator crashes or stops responding or intermittently slows down, or displays an error message about the Preferences folder being read-only, try resetting or deleting preferences. Before you proceed, create a backup copy of your existing preferences file.
When you reset preferences, the previous preferences file is saved as Adobe Illustrator Prefs.err.
macOS
Do one of the following:
Windows
Do one of the following:
You may require read and write permission to delete the preferences folder. If the issue persists, change the preferences folder permission to read and write or fix damaged preferences files in Windows.
Delete the preferences file at:
macOS:
Windows:
Example: /Users/<Username>/Library/Preferences/Adobe Illustrator 25 Settings
Folder names may vary based on the installed language version. A new preferences file is automatically created the next time you launch Illustrator.
Follow the instructions given below to provide read and write permissions to Adobe folders.
macOS
Perform this procedure, once each for the following folders:
Windows
Perform this procedure, once each for the following folders:
In folder paths or names listed in the procedures, replace the parts between angular brackets '<>' with the details required:
You may need Administrator permissions on your computer to complete the following procedure.
On your Windows-based computer, choose Windows > Run or press Windows+R.
In the Run dialog, type intl.cpl and press Enter.
In the Region dialog, select Administrative tab, click Change system locale.
In the Current system locale drop-down, select English (United States), and press OK twice.
Start Illustrator. The steps performed so far should fix the issue with the Preferences file in Adobe Illustrator. Proceed to the next step if you continue to experience an error with the corrupted Preferences file.
Repeat Steps 1 and 2. In the Region and Language dialog > Formats tab, click Additional settings.
In the Customize Format dialog, ensure that the:
Restart Illustrator.
To avoid preferences-related issues in the future:
To preempt any performance issues after updating to a new version,
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