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Folder Rules guide

Rename matching files automatically on Windows

Use Folder Rules to add a prefix to matching file names, test the result, and prevent the same prefix from being applied repeatedly.

By Osenpa · Updated · Reviewed
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Short answer

In Folder Rules, match a narrow set of files, choose Rename, and choose a Name adjustment such as Add text at the start. Preview before saving. Make the rule stop matching its renamed output so a later check cannot add the same prefix again.

Before you start

  • Folder Rules from Microsoft Store and Windows 11 24H2 or later on an x64 PC.
  • A test folder on a fixed local NTFS drive outside cloud/sync folders and network shares. Check File system in the drive's Properties in File Explorer.
  • Two harmless text files named note-one.txt and note-two.txt, plus an unrelated PDF that should stay untouched. Use copies for this first test.

Start here

  1. Choose the sample folder

    In Folder Rules, select Choose folder and choose the test folder. Select Add rule and enter a Rule name such as Mark reviewed notes.

  2. Match the original names only

    Set Item type to File and enter txt in File extensions (optional). Under More conditions, enter note-*.txt in Name pattern (* and ?). The asterisk matches the rest of the name. Leave Include subfolders off.

  3. Add a prefix

    Under Do this, choose Rename. Set Name adjustment to Add text at the start. Enter Reviewed- in Text to add at the start. Set If the name already exists to Keep both. Renaming changes the name in the current folder; it does not need a destination.

  4. Preview, then save

    Select Preview. Confirm that note-one.txt and note-two.txt match, but the PDF does not. Select Save rule only when this scope is correct. Saving checks existing matches as well as new files once they are ready.

  5. Check names and contents

    Read Activity and inspect the folder. With no name conflicts, the files should be Reviewed-note-one.txt and Reviewed-note-two.txt. Open both to confirm their contents are unchanged. The PDF should keep its original name. Pause the app or switch this test rule off when the exercise is finished.

Check your result

  • Only the two intended text files were renamed; the PDF stayed untouched.
  • The new names begin with Reviewed-note-, so they no longer match note-*.txt.
  • Both renamed files open with the expected contents, and Activity has no unresolved outcome.

Why the name pattern matters

A rule that matches every txt file can still match a file after adding a prefix. The sample deliberately requires a name beginning with note-. Reviewed-note-one.txt no longer begins that way, so this rule will not keep adding Reviewed- on later checks.

When adapting the example, choose conditions that exclude the finished name. Preview again after changing the pattern or adjustment; do not use your only copies as the test.

If the new name already exists

Keep both chooses an available different name instead of replacing the existing item. Read Activity and inspect the actual result rather than assuming a fixed numbered suffix.

If you choose Skip instead, a conflicting item can remain with its old name. Check the outcome before repeating the operation.

If the intended rule does not run

Every condition must match, and an earlier matching rule controls the action. Check the rule order, extension and name pattern, then inspect Activity for a waiting or unsupported-item reason.

Use Add text at the end or Prefix with last modified date only when that is the naming result you need. Test the chosen adjustment separately instead of combining an untested naming change with other folder work.

The app used in this guide

Folder Rules

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Related guides

Sources and further reading