Articles on: Optimizer Tweaks

What Show File Extensions does in eclean Optimizer

Shows file extensions for known file types in Explorer, making it easier to identify real file formats and spot misleading filenames.


Use this article before applying Show File Extensions in Optimizer so you know what the tweak is meant to change, what result to expect, and how to undo it if the change does not fit your setup.


How to apply this tweak


  1. Open Optimizer: Go to the Optimizer page in eclean.
  2. Find the tweak: Search for Show File Extensions or open the category where it appears.
  3. Read the card: Review the description, current state, restart requirement, and any warning pills on the tweak card.
  4. Open more information if needed: Click the information icon when you want the full context before changing it.
  5. Add it to pending changes: Toggle Show File Extensions. eclean adds the change to pending changes instead of applying it immediately.
  6. Review the pending list: Open the pending changes pill and confirm the list contains only the tweaks you intend to apply.
  7. Apply the change: Click Apply and confirm any warning dialog eclean shows.
  8. Check the result: Open Optimizer History after the action finishes, then restart Windows or Explorer if eclean says a restart is required.


What can change


  • Expected result: Shows file extensions for known file types in Explorer, making it easier to identify real file formats and spot misleading filenames.
  • Categories: Usability, Security
  • Scope: Current Windows user profile
  • Warning labels: No warning label registered
  • Restart requirement: Windows Explorer restart required
  • Compatibility: No minimum Windows build registered
  • Windows policy, another tuning tool, or a different Windows build may block, restore, or change how the setting behaves.


If the tweak does not behave as expected


  • Open Optimizer History and check whether the result was completed, blocked, unsupported, failed, or unverified.
  • If the tweak is blocked, check whether the PC is managed by work, school, antivirus policy, or another system management tool.
  • If a Windows feature you use stops working, return to Optimizer and revert this tweak before changing unrelated settings.
  • If the setting still looks unchanged after a successful result, restart Windows and check again.


How to revert it


  1. Return to Optimizer: Find Show File Extensions again.
  2. Toggle it back: Add the reverse change to pending changes.
  3. Apply the revert: Review pending changes, click Apply, and confirm any warning dialog.
  4. Verify afterward: Check Optimizer History and restart if the tweak requires it.


Advanced technical details


This section is for advanced users who want to audit the change or reverse it without opening eclean. Registry paths under HKLM usually require administrator access.


What eclean changes


  • Sets HideFileExt to 0 so Explorer displays extensions for known file types
  • Sets HideFileExt to 1 when disabled to restore the Windows default
  • Registry value or key: HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\HideFileExt


Manual revert without eclean


Use Optimizer History when possible. If you revert manually, restore or remove the Windows settings listed above according to your desired Windows default, then restart Windows or Explorer if the tweak requires it.


Important note


This tweak changes a supported Windows setting. It does not guarantee better results on every PC, and it should be reverted if it conflicts with a feature, device, game, app, or policy you rely on.

Updated on: 12/06/2026

Was this article helpful?

Share your feedback

Cancel

Thank you!