Equisys technical notes

Technical guidance, explanations and fixes for our products

PRB: CAPI reports 'An error occurred while closing connection' with AVM card



ID: ZTN1677

This Zetafax technical note applies to:

  • Zetafax 2006 and later
  • AVM-C4 ISDN cards although other AVM cards may be affected


Zetafax is configured with an AVM card using its CAPI driver. When a fax is sent it is received by the recipient, however Zetafax will continue to send the fax multiple times as CAPI reports an error in transmission:

CAPI-1 -(W)- An error occurred while closing connection

CAPI-1 -(E)- Error UNABLE TO CONNECT OR NO ANSWER sending message to remote


There is an incompatibility between the AVM card and the Zetafax CAPI driver.


This card can’t be used reliably with Zetafax and we recommend switching to another active ISDN controller.


This has been identified by Equisys as a problem with the software versions given above.

Last updated: 8 April 2008 (GC/PS)

Keywords: < CAPI> < multiple faxes received>

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