The most recent maintenance operation (November 7, 2017) included cleanup activities that may have unintentionally removed your whitelisted IP addresses configured to access the remote desktop (RDP) port for all Microsoft managed non-production Sandbox (Tier 1 & Tier 2+) environments. If you have lost RDP access to your virtual machines, you will need to whitelist them again through LCS by navigating to the Environment page (Maintain -> Enable access). Please see https://docs.microsoft.com/en-us/dynamics365/unified-operations/dev-itpro/deployment/cloud-deployment-overview#features-of-the-finance-and-operations-production-instance for information on how to whitelist. We sincerely apologize for the inconvenience.
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