PRA Remote Mailbox 2.0.0

First public release.

PRA Remote Mailbox is a hybrid Exchange disaster recovery tool. When the on-premises Exchange servers are lost, it turns the on-premises mailboxes into remote mailboxes so that users get a mailbox in Exchange Online, and it rolls everything back when Exchange is available again. Active Directory and Entra Connect are the only systems changed on-premises.

Highlights

• One entry script driven by a configuration file: -Action Convert|Recover|Finalize|Check, -Mode Preview|Apply, -Batch <id>. Every run starts in Preview.
• Backup before any write, AD proofs and SHA-256 receipts, stop at the first error; Recover from a short batch ID.
• Shared mailboxes: FullAccess, SendAs and SendOnBehalf read from Active Directory and granted again in Exchange Online, groups expanded to their users (nested groups included), each right granted once then verified. Entries of deleted accounts are ignored and reported as warnings.
• Entra Connect delta sync, local or remote, checked before the first AD write.
• Readable console, log, transcript, CSV and self-contained HTML report; exit codes 0 / 1 / 2 (next step required).
• One server or two servers (AD part on-premises, cloud part elsewhere, Finalize package).

Validation

• Test gate: 279 / 279 tests passed (Windows PowerShell 5.1, Pester, PSScriptAnalyzer).
• Lab campaign on a real Active Directory, Entra Connect and Microsoft 365 tenant: 28 runs (guide, annex B).

Requirements

Windows PowerShell 5.1, RSAT ActiveDirectory, ExchangeOnlineManagement 3.10+, Microsoft.Graph.Authentication and Microsoft.Graph.Users.

Package

PraRemoteMailbox-2.0.0.zip contains only what is needed to run the tool and the guide (no tests or tools), with an empty configuration to fill in (guide, chapter 6).

Package updated on 2026-10-02

Same version, same files, no change to what the tool does: the README and the guide now start with a note to unblock the files downloaded from the Internet (Get-ChildItem "C:\Chemin\Du\Dossier" -Recurse -File -Force | Unblock-File). The Install-Module commands of the guide, and the one shown when ExchangeOnlineManagement is missing, use -Force, with what to do when an older module version still conflicts.