Something went wrong. There are too many active sessions connected to this mailbox.

Question

Hi guys,

I have Exchange Servers 2019 CU12.

I configured a Unlimited Throttling Policy to a specific OWA User, but is not working.

Follow my cmdlets used:

New-ThrottlingPolicy -Name OWA-UnlimitedPolicy -RCAMaxConcurrency 2147483647 -OWAMaxConcurrency 2147483647 -OutlookServiceMaxSocketConnectionsPerUser 2147483647 -OutlookServiceMaxSocketConnectionsPerDevice 2147483647 -OutlookServiceMaxConcurrency 2147483647 -EWSMaxConcurrency 2147483647 -MessageRateLimit 50 -RecipientRateLimit 5000

Stop-Service MSExchangeThrottling

Start-Service MSExchangeThrottling

C:\Windows\System32\Inetsrv\Appcmd.exe recycle apppool /apppool.name:"MSExchangeServicesAppPool"

C:\Windows\System32\Inetsrv\Appcmd.exe recycle apppool /apppool.name:"MSExchangeOWAAppPool"

C:\Windows\System32\Inetsrv\Appcmd.exe recycle apppool /apppool.name:"MSExchangeOWACalendarAppPool"

Set-Mailbox <E-MAIL> -ThrottlingPolicy OWA-UnlimitedPolicy

Get-Mailbox <E-MAIL> | Select ThrottlingPolicy

Get-ThrottlingPolicyAssociation -Identity <E-MAIL>

So, what i missed?

Thanks guys!

Answer 1

Hi @Evandro Boa Semedo ,

I think you could try to create a new Maximum Allowed Service Sessions Per User key value, but this may affect the settings of the Exchange server globally and may cause some performance problems.

Check this: Managed Store Limits in Exchange 2016 and Exchange 2019 | Microsoft Learn

Regards

Shaofan

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Answer 2

@Shaofan Lv-MSFTI tested in my lab and works fine, is necessary restarting the MSExchangeIS. Do you know why is not works using Throttling Policy, there is some limitation?