How to fix error: The following untracked working tree files would be overwritten by checkout in Git

First, examine the files Git lists in the error message. Determine if they contain important work you want to keep:

# The error message shows which files are affected, for example:
# error: The following untracked working tree files would be overwritten by checkout:
#     src/config.js
#     .env.local

Decide whether these files contain work you need to preserve or if they can be safely removed.

If you want to preserve the untracked files and restore them later, use git stash with the -u flag to include untracked files:

# Stash all changes including untracked files
git stash -u

# Now perform your checkout/rebase
git checkout target-branch
# or
git rebase main

# Later, restore your stashed files
git stash pop

Note: git stash pop may cause merge conflicts if the restored files conflict with the branch content.

If the files are not important (e.g., build artifacts, temporary files), you can remove them with git clean:

# First, do a dry run to see what would be deleted
git clean -n -d

# If the list looks correct, remove the files
git clean -f -d

# Now proceed with your operation
git checkout target-branch

Warning: git clean permanently deletes files. Always run with -n (dry run) first to verify.

If these files represent work that should be part of your repository, commit them first:

# Add the untracked files
git add src/config.js .env.local

# Commit them
git commit -m "Add configuration files"

# Now checkout/rebase will handle them as tracked files
git checkout target-branch

This converts the conflict from an untracked file issue to a normal merge conflict, which Git can handle.

For maximum safety, manually move the files out of the repository:

# Move files to a safe location
mv src/config.js ~/backup/
mv .env.local ~/backup/

# Perform your Git operation
git checkout target-branch

# Move files back if needed (they'll be untracked again)
mv ~/backup/config.js src/
mv ~/backup/.env.local .

This approach gives you complete control and doesn't risk losing any data.

If you're certain you don't need the untracked files, you can force the checkout:

# Force checkout - WILL DELETE untracked files that conflict
git checkout -f target-branch

# Or with git switch (Git 2.23+)
git switch -f target-branch

Warning: This permanently deletes the conflicting untracked files. Only use this if you're certain the files are not needed.