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Error: "Critical System Error System.FormatException Input string was not in a correct format"

This support note applies to:

  • AO Practice Manager (NZ)
  • AO Practice Manager (AU)
  • AE Practice Manager (NZ)
  • AE Practice Manager (AU)
Article ID: 28958

If negative number formats are incorrectly set in Windows, you may see the following error when adding a credit note/ a negative miscellaneous charge such as a discount or practice write off in MYOB Practice Manager.

Critical System Error
Input string was not in a correct format.

How to set the Negative Number Format
  1. In Windows, open Control Panel.

  2. Go to Clock, Language and Region > Region or Region and Language.

  3. Click Additional settings. The Customize Format window appears.

  4. From the Negative number format drop-down list, choose -1.1.

  5. Click OK. The changes are saved.

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