Mayank Pujara's AutoNumberUpdater plugin for the XrmToolBox is a great tool to add missing auto number values to an auto number field for an entity/table. In his blog you can find more details about the original version of his plugin: https://mayankp.wordpress.com/2021/12/09/xrmtoolbox-autonumberupdater-new-tool/ For my purposes I had to update accounts with missing account numbers, but in my use case this should only be done for those accounts that have the status value "Active". As this plugin did not have this feature I quickly implemented it and Mayank merged my changes to his plugin source code. You can download the new version 1.2024.0.1 in the Tool Library of the XrmToolBox.
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