why can't I sign in with my account on the tablet and it says that I don't have connections eventho my network here is fine?

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Dear @Najla Ayasha Hanivia,

Welcome to Microsoft Q&A Forum!

Based on your provided image, the error code 2604 and message Network infrastructure failure indicate that the client device could not reach Microsoft services due to a network issue. This typically occurs when:

• The device may be offline or has unstable connectivity.
• A firewall, proxy, or VPN is blocking Microsoft endpoints.
• DNS resolution or TLS inspection is interfering with Microsoft services.

Therefore, I have several suggestions that you can try to see if it can help:

1.Check basic connectivity to ensure the device has internet access (try browsing a public site). If you use Wi-Fi, test with a wired connection or another Wi-Fi network.

2.The issue may be related to network connectivity, which may involve firewall or proxy settings on your company’s network. Could you please contact your IT administrator and ask them to check the following:

• Ensure your device can access Microsoft endpoints such as:
  • https://login.microsoftonline.com
    • https://portal.office.com
    • Verify that no firewall, proxy, or VPN is blocking Microsoft services.
• Confirm DNS and TLS settings are correctly configured (TLS 1.2 enabled).
• If SSL/TLS inspection is in place, make sure Microsoft traffic is excluded.

Once these checks are complete, please try signing in again. If the issue persists, let us know and share any updates from your IT team.

3.While your IT team checks the network settings, you can continue working by using Word Online:

1. Go to https://www.office.com.
2. Sign in with your Microsoft account.
3. Open Word from the app list and start editing documents in your browser.

This will let you work without waiting for the desktop app to reconnect.

Besides that, I found a case that was partially similar to your situation, you can consult as well: https://learn.microsoft.com/en-us/answers/questions/4627275/real-fix-for-outlook-365-sign-in-error-2604-is-tls

I hope this information can help you and please feel free to update to me in the comment section.

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