# Unsigned application issue on Mac

**URL:** <https://discourse.slicer.org/t/unsigned-application-issue-on-mac/12930>\
**Category:** Support\
**Created:** [August 10, 2020, 5:07pm UTC](https://discourse.slicer.org/t/unsigned-application-issue-on-mac/12930 "2020-08-10T17:07:06Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [August 10, 2020, 5:07pm UTC](https://discourse.slicer.org/t/unsigned-application-issue-on-mac/12930/1 "2020-08-10T17:07:06Z")

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Posting on behalf of a user. He apparently installed the latest mac preview, but got this error message after trying to start Slicer.

> **“Slicer” cannot be opened because the developer cannot be verified. macOS cannot verify that this app is free from malware**

What is the proper way to override this?

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**Author:** ![hherhold](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/hherhold/32/12199_2.png) [@hherhold](https://discourse.slicer.org/u/hherhold)\
**Post date:** [August 10, 2020, 5:19pm UTC](https://discourse.slicer.org/t/unsigned-application-issue-on-mac/12930/2 "2020-08-10T17:19:26Z")

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1. Go find the app in Finder
2. Right click and say “Open”
3. When it says “this app can’t be opened” go ahead and hit cancel
4. Right click and say “Open” a second time. (Yeah, it’s like it didn’t listen the first time.)
5. Go ahead and click “Open anyway” or whatever it says.

Off you go.

You can also go to the privacy/security settings in the control panel, I think, and override there.

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**Author:** ![Reham\_Hassan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/reham_hassan/32/7824_2.png) [@Reham\_Hassan](https://discourse.slicer.org/u/Reham_Hassan)\
**Post date:** [August 10, 2020, 5:43pm UTC](https://discourse.slicer.org/t/unsigned-application-issue-on-mac/12930/3 "2020-08-10T17:43:52Z")

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Thank you, this actually worked

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**Author:** ![Charles\_Pierce](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/charles_pierce/32/11273_2.png) [@Charles\_Pierce](https://discourse.slicer.org/u/Charles_Pierce)\
**Post date:** [June 16, 2021, 6:16pm UTC](https://discourse.slicer.org/t/unsigned-application-issue-on-mac/12930/4 "2021-06-16T18:16:29Z")

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Thank you for this easy fix- had the same problem!