> For the complete documentation index, see [llms.txt](https://help.getupnote.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.getupnote.com/resources/troubleshoot-issues/cant-sign-in-to-account.md).
# Can't sign in to account
There are a few common reasons a login may not go through. Review the situations below and follow the steps that match what you’re experiencing to quickly regain access to your account.
### If you see the error message: `Error (auth/firebase-app-check-token-is-invalid)`
If you see this error when signing in, please update your app to the latest version and try again.
Go to **Settings > Help > Check for updates** to update the app, or follow the links below:
* [Windows - Microsoft Store](https://www.microsoft.com/en-us/p/upnote/9mv7690m8f5n?activetab=pivot:overviewtab)
* [Windows - installer](https://download.getupnote.com/app/UpNote%20Setup.exe)
* [Mac](https://itunes.apple.com/us/app/upnote-an-elegant-note-app/id1398373917?ls=1\&mt=12)
If you have more than one UpNote installation on your device, please remove all versions and reinstall a single copy to ensure everything works properly.
### Unable to sign in with Google or Apple
Try hovering over the “Sign in with Google/Apple" button and clicking the pop-out icon to open the link in your browser to sign in.
### Forgot password
* Follow [this guide](/get-started/manage-your-account/reset-password.md) to reset your password.
* If you don’t see the password reset email, please make sure you’re using the latest version of UpNote and check your mailbox’s spam or junk folder.
***
Still need help? [Contact us](/resources/contact-us.md) and we’ll assist you further.
---
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