步骤：

1、备份原有Exchange数据库

2、重新安装Exchange

3、恢复数据库

过程：

重新安装Exchange

在ECP中创建数据库，创建时不要选择“装入数据库”

然后，下面是在命令行创建的过程

例子设置属性重写时注意是数据库名字，下图

连接到原有数据库之后，用下面命令把原有的数据导入到用户的数据库中，具体如下：

Get-MailboxStatistics -Database 'Mailbox Database 0812370482' | Where {$_.DisconnectReason -eq "SoftDeleted" -or $_.DisconnectReason -eq "Disabled"} | Format-List LegacyExchangeDN,DisplayName,MailboxGUID, DisconnectReasonNew-MailboxRestoreRequest -SourceDatabase "Mailbox Database 0812370482" -SourceStoreMailbox f2d02cc9-64ca-4c6e-b197-d33653eb73db -TargetMailbox noreply -AllowLegacyDNMismatch

下面命令参考

Get-Mailbox -Database 'Mailbox Database 0657806174' |where {$_.ObjectClass -NotMatch '(SystemAttendantMailbox|ExOleDbSystemMailbox)'}| Set-Mailbox -Database 'Mailbox Database 0812370482'Add-MailboxPermission -Identity "cndw" -User cndw -AccessRights FullAccess -InheritanceType All

相关文档：https://learn.microsoft.com/en-us/powershell/module/exchange/get-mailboxpermission?view=exchange-ps

https://learn.microsoft.com/en-us/powershell/module/exchange/new-mailboxrestorerequest?view=exchange-ps