Sometimes you will need to get a list of users (delegates) that have access to other mailboxes (delegated mailboxes). Exchange 2010/2013 provides Get-MailboxPermission cmdlet that can query mailboxes for permissions. 

You can extend use of cmdlet to all mailboxes:

In Exchange you can encounter issues when you move mailbox between databases. And after this issues you can have, for example, 2 (or several) mailboxes in your databases which belongs to a single user. And of course, only one mailbox from them linked to Active Directory user account.

And one more thing - mailboxes that are not used, NOT marked as Disconnected or SoftDeleted.

These mailbox are known as ghost-mailboxes.

You can expect the following errors while running Get-MailBox, New-MoveRequest and many other commanlets in Powershell in EMS (Exchange Management Shell):

The requested search root domain is different from the scope root domain.

or

The requested search root domain.local/Users’ is not within the scope of this operation. Cannot perform searches outside the scope ‘child.domain.local’.

Exchange 2010 has the concept of internal and external URL's for various virtual directories for the Client Access Server (CAS role).

You must correctly specify values for URLs because of potential issues with certificates and discoverability of Exchange services for your users.

Here are commandlets in powershell to control all virtual directories URLs in Exchange 2010 (most or all of them are also will work in Exchange 2013):

I've faced problem when user logged on computer running Windows XP, cannot enroll certificate from Certification Authority running on Windows Server 2012 R2.

First, enroll wizard didnt start at all, and then it start but at the final step access error was shown.

When you want to set up SSL in Apache 2, you will need to provide to the service the following items: certificate for web-site, private key for that certificate, root CA certificate that issued web-site-certificate.

In my case I got from our sequrity-men p12-file which contains certificate itself and the private key. How to convert this p12 bundle to RSA private key?