0X800706BA

The RPC server is unavailable.

Symbol / family

RPC_S_SERVER_UNAVAILABLE

Signed decimal

-2147023174

Unsigned decimal

2147944122

What it means here

The client could not reach or establish RPC communication with the target service or host.

What to check next

1. Verify name resolution, reachability, required services, and endpoint mapper access.
2. Check Windows Firewall and network controls for the RPC endpoint and dynamic port range.
3. Confirm the target service is listening before retrying remote administration.

Technical reference: Microsoft documentation or Microsoft-hosted support material