Add Server rejects valid hostnames using uncommon TLDs such as .sarl with U-000 error

Summary

The Add Server interface rejects valid and resolvable hostnames that use certain uncommon top-level domains, such as .sarl.

When www.lilith-is-all-you-need.sarl is entered directly, the Add Server screen does not close, the server is not added, and a U-000 error is displayed.

The same hostname can successfully resolve and connect after the UI validation state is triggered using another address first. This indicates that the hostname and DNS record are valid, and that the failure is likely related to address validation or validation state in the Add Server interface.

This may be related to MCPE-194696.

Steps to Reproduce

1. Open the Servers tab.

2. Select Add Server.

3. Enter any server name.

4. Enter the following address in the Server Address field:www.lilith-is-all-you-need.sarl

5. Select Save or Play.

Observed Result

• A U-000 error is displayed.

• The Add Server screen remains open instead of returning to the previous screen.

• The server entry is not added successfully.

• The normal connection process does not begin.

This behavior differs from other inputs:

• A valid hostname using a common TLD proceeds to the normal connection process.

• Other invalid or fabricated addresses are handled through the normal UI flow, such as displaying the standard “Invalid server address format” warning or returning to the previous screen.

• The valid .sarl hostname instead triggers U-000 and prevents the server from being added.

Expected Result

A syntactically valid hostname using a delegated TLD should be accepted regardless of how common the TLD is.

www.lilith-is-all-you-need.sarl should be passed to the normal DNS resolution and connection process, just like a hostname using .com, .net, or another commonly used TLD.

Workaround

The issue can be bypassed by triggering the normal validation state before entering the .sarl hostname:

1. Open the Add Server screen.

2. Enter an invalid address such as:12345

3. Allow the UI to display the standard “Invalid server address format” warning.

4. Without closing the Add Server screen, replace the invalid address with:www.lilith-is-all-you-need.sarl

5. Select Play.

The game then accepts the same hostname, resolves it, and successfully connects to the server.

Additional Information

The workaround demonstrates that:

• The hostname is resolvable.

• The server is reachable.

• The networking and DNS connection process can use the address successfully.

• The failure depends on how the address is initially processed by the Add Server UI.

This suggests that the issue is in the address-validation logic or its UI state handling. One possible cause is a TLD allowlist or an overly restrictive hostname-validation rule, but confirming the exact implementation would require internal logs or source code.

Reproducibility

Consistently reproducible

• Entering the .sarl address directly results in U-000.

• Triggering the validation warning first and then replacing the input with the same .sarl address allows the connection to succeed.