Equisys Technical Notes

Technical guidance, explanations and fixes for our products

PRB: Unable to install 4 line add-on with older Zetafax systems



ID: ZTN1373

This Zetafax technical note applies to:

  • Zetafax version 8 or earlier


When attempting to install a 4 line add-on on a Zetafax 8 or earlier system, the Zetafax Configuration program rejects the licence number with the following error message:

'The upgrade or add-on number you have specified is invalid, or has been typed in incorrectly'.


The 4 line add-on was introduced with Zetafax 9, and is not recognised directly by older systems.


The licence number for a 4 line add-on has the format " Uxxxxxxx-LINE4-xxxxxx" .  To enter this with Zetafax 8 or earlier, replace the text LINE4 with the letters AAAEAA.



should be entered as



This is designed behaviour, caused by an enhancement in a later product release

Last updated:  6th July 2004 (IM/GW)

Keywords: Additional line, additional lines, add-on, setup, licencing


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