To resolve the "No connection to server" issue with TeleGuard, follow these steps to troubleshoot and fix the problem:

1. Check Internet Connection
- Ensure your device is connected to the internet. Test by opening a web browser and visiting several websites. If there’s no connectivity, troubleshoot your network settings.

2. Restart Your Device
- Restart your iPhone to refresh the network settings. Sometimes this simple step resolves connection issues.

3. Adjust Network Settings
- If you're connected to Wi-Fi, try switching to cellular data or vice versa. This can help identify if the issue is with a specific network.

4. Check App Permissions
- Go to Settings > TeleGuard and ensure all necessary permissions are granted, particularly for network access.

5. Network Troubleshooting
- If your phone is on the same network as the server that TeleGuard is trying to connect to, ensure there are no restrictions set on the router that could prevent connections.
- As reported, the error can sometimes occur due to network configurations, especially if your router has been updated or changed recently.

6. Reinstall TeleGuard
- If the problem persists, uninstall and then reinstall the TeleGuard app. This can help resolve issues related to corrupted app data.

7. Check for Server Status
- Visit any official TeleGuard forums or support pages to ensure that the server is up and running. There may be outages or maintenance affecting connectivity.

8. Consult Community Resources
- If you've followed the above steps and still face issues, you might want to refer to user discussions on platforms like Reddit, where similar issues have been addressed:
- "No connection to server. Functionality will be limited. Any way to fix" - learn more.

9. Contact Support
- If none of these methods work, it may be beneficial to contact TeleGuard support for further assistance, as there might be more specific issues affecting your device or account.

By following these steps systematically, you should be able to identify and resolve the connection issue with TeleGuard.