Error Message: "Port in Use" or "Port Already Open"

 Last reviewed: December 15, 1997
Article ID: Q168222
The information in this article applies to:
  • Microsoft Windows 95

SYMPTOMS

When you attempt to start a communications program, you may receive one of the following error messages:

  • Error: port in use
  • OpenComm: Port already open

CAUSE

This behavior can occur if Rnaapp.exe is active in memory.

RESOLUTION

To work around this issue, follow these steps:

  1. Press CTRL+ALT+DELETE to open the Close Program dialog box.

  2. Click Rnaapp to select it, and then click End Task.

  3. Start your communications program.

MORE INFORMATION

When you finish using a communications program and close the connection, Rnaapp.exe is still running and the port remains unavailable to non-TAPI programs.

Rnaapp.exe is left in memory to allow TAPI programs to open faster. Rnaapp.exe is eventually unloaded from memory (unless Dial-Up Networking Server is set to allow caller access), but it may take 10-15 minutes.

Additional query words: 95
Keywords : dun win95 wincomm wintapi kberrmsg kbtool
Version : 95
Platform : WINDOWS

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Last reviewed: December 15, 1997
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