when i run the connect-exchangeonline to connect it it should open a authentications window but it gives the error A window handle must be configured. See https://aka.ms/msal-net-wam#parent-window-handles At C:\Program Files\WindowsPowerShell\Modules\Exc
when i connect-exchangeonline i get this error : A window handle must be configured. See https://aka.ms/msal-net-wam#parent-window-handles At C:\Program…
How to convert an user account with Mailbox to M365 group without losing data
Hello All, Is there a way to convert an existing user mailbox to M365 group without loosing the mailbox data.
The file size limits of .pst and .ost in Outlook Office 365 ?
what is the limit of *.ost or *.pst file in outlook in office 365
Can't revert from "Mail User" to "User Mailbox"
Hello, One of my users lost complete access to her mailbox, I believe her Office licence got "removed" for 2~ hours then put back but nothing came back to normal... O365 Admin Center shows this message on their profile : Exchange : The…
Can Exchange server and office 365 coexist?
Hi, So, to give you an idea of what is our situation. We are a small business with a limited number of users. Currently we have an exchange e-mail address for all users. We would like to migrate two of our users to office 365, their mail address may…
Exchange server 2019 CU15 setup command question with best practice
Dear Sir, Customer has Exchange 2019 server running, they want to install CU15. Do it has any suggestion whether it is fine using below command? ```E:\Setup.exe /IAcceptExchangeServerLicenseTerms_DiagnosticDataOFF /Mode:Upgrade /DonotEnableEP Do it…

Recent Exchange Calendar Sync Issues with iOS Devices, Exchange 2019 & 9646 Errors
Title: Exchange Calendar Sync Failures for some users with ExchangeIS 9646 App Log Errors Details: We have ~ten or so users that have reported calendar sync issues using Exchange On-Prem, iOS Native Calendar and our MDM (Ivanti MobileIron) over the past…
Duplicating mails in exchange online in junk folder
Hey, we have a problem with duplicating mails in actually four tenants: Exchange online is duplicating spam mails itself, u can see, it was only once delivered to Exchange Online, but it's delivered to junk mail repeatedly! At some addresses it's only…
When DelegateSentItemsStyle is set, the Mail is always stuck in Outbox
We saw online on TechNet, that it is possible to send a mail in the name of a shared Mailbox and we tried to save the mail in the sent items in the shared Mailbox, cause we don't need a copy in the primary Mailbox. I attached an image from TechNet,…
Generic emails with @shadow.outlook.com on Random emails from Andriod devices with On prem mailbox
Hello, One of our users have this recurring issue that a generic email address ending with @shadow.outlook.com appears on the emails, that are sent using outlook app from an Andriod device. The email configured is hosted on an on-prem Exchange 2019…
Outlook.com to Microsoft 365 Migration failed
I'm trying to migrate my Outlook.com email to Microsoft 365 with IMAP Migration, but it keeps failing with this error. Error: ImapAuthenticationException: The username or password for this account is incorrect, or IMAP access is disabled. --> Imap…
Impossible to revert "Mail User" to "User Mailbox"
Hello, One of my users lost complete access to her mailbox, I believe her Office licence got "removed" for 2~ hours then put back but nothing came back to normal... We are using Exchange 2019, Active Directory and Azure. O365 Admin Center shows…

Outlook for iOS and Android is unable to connect to Exchange 2019
Outlook for iOS and Android is unable to connect to Exchange 2019. After adding the account, an error during authentication is displayed, please try again later. The built-in mail app of the mobile phone can connect, send, and receive emails normally.
Mitigations Cloud endpoint is not reachable Exchange 2019 Deployment
I receieve below warning during Exchange 2019 deployment Mitigations Cloud endpoint is not…
when adding send on behalf to a distribution list i get the message try again later
Hello Please i need your help on this issue. when adding send on behalf to a distribution list i get the message "try again later"
Users Unable to Access Webmail or Outlook After Upgrading Exchange 2019 to CU15
Hi Everyone, After upgrading Microsoft Exchange Server 2019 to CU15, some users from different locations are facing issues accessing their email through webmail (OWA) and Outlook mobile app. Here are the specific problems we're encountering: Webmail…
How to connect Microsoft Exchange Mail Accounts with our web application via Entra App
Dear Microsoft-Team, we are reaching out regarding authentication issues with our app registration for Microsoft Exchange integration. We want to connect Microsoft Exchange Mail Accounts with our web-application GetGenius, to be able to read and…
How to fix Delivery has failed to these recipients or groups
I have tried to send email for a company and a person which isn't the first-time sending emails to each other but recently when I try to send emails back to them, I mails bounces back and show the below message. knowing that we have sent emails to each…
Microsoft’s Exchange & @hotmail.com / @outlook.com domains Spam problem.
The email sent from a Microsoft’s Windows virtual machine using an application written in Microsoft’s Visual Studio and using the Microsoft’s SMTP server received at @yahoo.com and @googlemail.com, but it didn't even end up in the Junk Email at…
Mail Flow in Hybrid Deployment When HQ Goes Down
Hello, We currently have a Hybrid Exchange deployment with three Exchange Server 2019 Mailbox servers in our HQ, and we also have a DR site with another three Mailbox servers as part of the same DAG. I already understand how mail flow works between our…