BUG: DCOMCNFG Writes Ports Named Value in Incorrect Format

The DCOMCNFG utility writes the port range specified for a protocol in a incorrect format.

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

When a port range is specified for a protocol, such as 4000-4010, the value that is written to the registry key HKLM\SOFTWARE\Microsoft\RPC\Internet\Ports (named REG_MULTI_SZ) is "4000 - 4010." A space is added preceding and succeeding the "-". Remote Procedure Call (RPC) is extremly sensitive about the string format and fails the RpcServerUsePortSeq call with RPC_S_OUT_OF_RESOURCES. As a result, no client can talk to the server, and services such as Internet Information Server (IIS) do not start.

Steps to Reproduce Behavior

1. Run the DCOMCNFG and click the Default Protocol tab.
2. Select the protocol, and add a port range to it.
3. Check the registry entry. You will see an incorrect port range format.