What Microsoft sign-in does
Players with applicable game entitlement can authenticate a Minecraft: Java Edition identity with a Microsoft account. RMCL uses the sign-in result and related services to obtain game profile information and prepare launch details for the chosen identity.
The launcher does not sell or grant game entitlement. A local account is not an official online identity.
Sign-in and service access
Microsoft sign-in depends on valid application registration, correct configuration and access to the relevant Minecraft services. Software availability and service access are separate matters.
RMCL is an independent launcher. This page explains the sign-in flow and access errors; it does not imply certification, sponsorship or endorsement by Minecraft or Microsoft.
During sign-in
Add a Microsoft account from the account menu and follow the real Microsoft sign-in page. Check its source and requested permissions. Do not send passwords, verification codes or device login codes to maintainers or public issues.
For account help, use Microsoft account support. For purchasing, downloading and Minecraft account help, use the Minecraft website.
Application not configured or service access fails
Keep the original error and the step where it occurred, then check current project announcements. Application registration and service restrictions are not usually fixed by deleting worlds, changing Java or repeatedly signing in.
There is no need to borrow another launcher's application identity. Follow Feedback and logs, removing tokens, codes and personal information.
Child accounts and multiplayer
Family controls, Xbox privacy settings and the server's own requirements can affect multiplayer. The account holder or family organizer may need to use the relevant official settings. RMCL cannot replace those decisions.
Without Microsoft sign-in
You can still manage existing instances, configure runtimes manually, edit skins and use local identity where applicable. Servers or online services requiring an authenticated identity still require it.