Error3 reports
Fix InvalidCharacterError
in Next.js
✅ Solution
This error, InvalidCharacterError: Invalid character, typically arises in Next.js when route segments or group names contain characters outside the Latin-1 character set, a regression in Next 15. To fix it, ensure all your route segment and group folder names exclusively use standard ASCII characters. Avoid special characters, accents, or non-English alphabets in these directory names to prevent the error.
Related Issues
Real GitHub issues where developers encountered this error:
Route groups / segments with non-Latin-1 characters crash with `InvalidCharacterError: Invalid character` (regression from Next 15)Aug 25, 2026
Route groups / segments with non-Latin-1 characters crash with `InvalidCharacterError: Invalid character` (regression from Next 15)Aug 25, 2026
Route groups / segments with non-Latin-1 characters crash with `InvalidCharacterError: Invalid character` (regression from Next 15)Aug 25, 2026
Timeline
First reported:Aug 25, 2026
Last reported:Aug 25, 2026