# I can't log in or synchronize data

If you cannot log in to Termius or synchronize your data, and you see a spinner or an error message, check the following:

1. Make sure your firewall allows incoming and outgoing traffic for these domains: **api.termius.com**, **grpc.termius.com**, **account.termius.com**, **termius.com**, and **termi.us**. Also make sure these domains are reachable from your network.
2. Check whether your network performs TLS interception. This can break the **WebSocket** connection. If needed, add an exception for Termius domains.
3. Make sure the connection to **grpc.termius.com** uses HTTP/2. Termius requires it to work correctly.

If the issue persists, please [submit a support request](https://support.termius.com/hc/en-us/requests/new).


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.termius.com/help-center/troubleshooting/i-cant-log-in-or-synchronize-data.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.