where the data classification management has been moved to in this updated compliance portal experience

@Ganapathy Ram - Thanks for the question and using MS Q&A platform.

Note: All solutions and features will soon be completely migrated to the Microsoft Defender portal, Microsoft Purview portal.

You can find data classification in the Microsoft Purview compliance portal or Microsoft Defender portal > Classification > Data Classification.

For more details, refer to How to use the Microsoft data classification dashboard

The issue on Creating Custom classifiers will be resolved by opting to upgrade to the new Purview version by filling in the form below. The improved version will replace the existing instance of the Trainable Classifier feature, and the benefits are to be expected are:

• Faster training time, with no need for a background model to be created prior to the custom classifier creation.
• Simpler sample document gathering – only a positive sample set, and negative sample set is required at the beginning of training.
•  Automatic testing - No longer is a test set of both positive and negative samples required at the testing stage. Now this is automatic.
• More clarity around the trainable classifier creation flow and results.

Kindly Note that existing custom trainable classifiers that were created prior to this feature and currently unpublished will no longer be available.

 If you wish to turn on the new Purview Version of Purview, kindly fill this form and we will have the new version enabled for you.

Hope this helps. Do let us know if you any further queries.

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