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Error 'System.NullReferenceException Object reference not set to an instance of an object' when accessing AO

This support note applies to:

  • AO Practice Manager (NZ)
  • AO Practice Manager (AU)
  • AO Tax (AU)
Article ID: 34479

If you receive the error "System.NullReferenceException Object reference not set to an instance of an object" when accessing MYOB AO after an upgrade, you may be missing a file Lookup.xml which is normally located within the deploy folder.

To resolve this error, contact us and quote the KB number 34479.


You will need to edit a copy of a lookup.xml file which is normally located under their MYOBAO\AOSQL\Central>Deploy folder on the server.  

You need to add their server name and database name before emailing to client as below.  The fields to edit are in bold black:

<?xml version="1.0" encoding="utf-8"?>
 <ConnectionString Key="0" String_Value="Data Source=Server1\MYOBACCT;Database=AODB1;User ID=VPMUSER;PWD=BelfrY18">
<Description>Data on Server1\MYOBACCT</Description>
  <Plugin name="AEPracticeManagerPlus">


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