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Error: "Client is unavailable.System InvalidCastException. Conversion from type'DBNull..."

This support note applies to:

  • AO Tax (NZ)
  • AO Practice Manager (NZ)
  • AO Practice Manager (AU)
  • AO Tax (AU)
  • AE Practice Manager (NZ)
  • AE Practice Manager (AU)
  • AE Tax (NZ)
  • AE Tax Series 6 & 8 (AU)
  • AE Tax (AU)
Article ID: 34111


In Accountants Enterprise (AE) or Accountants Office (AO), you may receive the error "Client is unavailable. System InvalidCastException. Conversion from type'DBNull' to type 'String' is not valid" when trying to open a client.

The following error may appear thereafter "Cannot Delete Client/Supplier. Cannot insert the value NULL into column 'LNAME', table VPMSER.dbo.DeleteClients', column does not allow nulls. INSERT fails. Transaction count after EXECUTE indicates a mismatching number of BEGIN and COMMIT statements. Previous count=1, current count=0. The statement has been terminated".

The client may also display in the search screen as an active client but displays Closed on the client screen.

To resolve these error click OK to close the error message. To access the client details, click Edit client details and fill in the details for example, the name and click OK to save.


S/R 11911944283

Check that the client has access to the Main tab in order to gain access to the 'Edit client details' option. 


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