> For the complete documentation index, see [llms.txt](https://enterprise.hideez.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://enterprise.hideez.com/faq/hideez-client-app/what-do-i-do-if-the-connection-with-the-hes-server-cannot-be-established.md).

# What do I do if the connection with the HES server cannot be established?

a) Check that the server address is correct.

In case of changing the server address, do not forget to change the server address in the Hideez Client interface.\
\
Go to the **Settings > Hideez Enterprise Server** fill in or change the HES server address and click **Save**.

If you don't know the HES server address - ask your Administrator.

![](/files/lrlg7NRbjo0fgvMCQdBB)

b) Check that the Hideez service is running, restart it.

![](/files/dQUOFdRs2gk75erMKkEG)