Microsoft KB Archive Search

Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

  1. Home
  2. PRB: DCOM Does Not Work over Network Address Translation-Based Firewall

PRB: DCOM Does Not Work over Network Address Translation-Based Firewall

Symptoms

When you try to make Distributed Component Object Model (DCOM) calls over a Network Address Translation (NAT)-based Firewall, you receive the error 0x800706BA (RPC_S_SERVER_UNAVAILABLE).

↑ Back to the top

Cause

For DCOM to work, the client must be able to reach the server by its actual IP address. If you use firewalls that translate network addresses, the client cannot use the actual IP address to reach the server.

COM inserts the IP address of the server computer into the interface marshaling packets that are returned to the client. Instead of using the translated IP/header, Remote Procedure Call (RPC, or DCOM) uses the actual IP address to reach the server. Because the firewall prevents the client from directly accessing the server, the client receives the above-mentioned error message.

↑ Back to the top

References

For more information on using DCOM with firewalls, see the following Microsoft Web site:
http://www.microsoft.com/com/wpaper/dcomfw.asp
For additional information, click the article numbers below to view the articles in the Microsoft Knowledge Base:

154596 HOWTO: Configure RPC Dynamic Port Allocation to Work with Firewall
193230 PRB: Server.CreateObject Fails When Object Is Behind Firewall
249726 HOWTO: Search for COM and DCOM Knowledge Base Articles

↑ Back to the top

Keywords: kbclient, kbclientserver, kbdcom, kbdsupport, kbprb, kbserver, kbbillprodsweep, kb

↑ Back to the top

Article Info
Article ID : 248809
Revision : 3
Created on : 4/20/2018
Published on : 4/20/2018
Exists online : False
Views : 156