How can I recover Kusto data that was deleted due to a previous two-month retention policy?

Hi Allen Yu,

Thank you for posting your question on Microsoft Q&A. We’ve reviewed it and prepared a clear, step-by-step solution to help resolve your issue.

Need to Know About Recovering Kusto Data Retention Policy Basics The retention policy controls how long your data stays available for queries before it’s deleted. Two key settings matter here: • SoftDeletePeriod: This is the guaranteed time your data remains query able. • Recoverability: If this was turned on, you have a short window—about 14 days after deletion—to recover the data. Retention policy - Kusto | Retention policy - Kusto | Microsoft Learn What Happens After Retention Expires? Once the retention period ends and the 14-day recovery window passes, the data is permanently removed. There’s no built-in way to restore it from Azure Data Explorer at that point. How do I recover data deleted from a table ? - Microsoft Q&A If You’re Still Within the 14-Day Window You can raise a support ticket through the Azure portal. Make sure you include details like: • Table name and cluster • Approximate deletion time • Client Activity ID (from .show commands-and-queries) If you dropped a table by mistake, you can use the .undo drop table command—again, only if you’re still within that recovery window. If It’s Beyond 14 Days or Recoverability Was Off Unfortunately, the data can’t be recovered. Your only option is to restore from external backups or exports (for example, if you had set up continuous export to Azure Blob or Data Lake). Why Changing Retention Now Doesn’t Help Extending the retention period to six months only applies to data that’s still in the system. It won’t bring back anything that was already deleted under the old two-month policy. What You Can Do Next • Check Your Current Policy Run: PowerShell .show table [TableName] policy retention confirm if Recoverability was enabled. • If You’re Within 14 Days Act fast—open a support ticket and try .undo drop table if needed. • For the Future Set up continuous export to external storage for long-term backups and consider cache policies for better data management. How do I recover data deleted from a table ? - Microsoft Q&A

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Thanks, Vrishabh