Set up Exchange Online as an SMTP Relay Using Windows Server 2012 / 2012 R2

Set up Exchange Online as an SMTP Relay Using Windows Server 

1. Install Internet Information Services (IIS)
   1. In Server Manager, select Add Roles.
   2. On the Before you begin page in the Add Roles Wizard, select Next.
   3. On the Select Installation Type page, select Role-based or Feature-based installation.
   4. On the Select destination server page, choose Select a server from the server pool, and select the server that will be running SMTP services. Select Next.
   5. On the Select Server Roles page, select Web Server (IIS), and then select Next. If a page that requests additional features is displayed, select Add Features and then select Next.
   6. On the Select Role Services page, make sure that Basic Authentication under Security is selected, and then select Next.
   7. On the Confirm Installation Steps page, select Install.
2. Install SMTP
   1. Open Server Manager and select Add Roles and Features.
   2. Select Server Selection and make sure that the server that will be running the SMTP server is selected and then select Features.
   3. On the Select Features screen, choose SMTP Server. You may be prompted to install additional components. If that’s the case, select Add Required Features and select Next.
   4. Select Install. After the installation is finished, you may have to start the SMTP service by using the Services snap-in for the Microsoft Management Console (MMC).
3. Set up SMTP
   1. Open Server Manager, select Tools, and then select Internet Information Services (IIS) 6.0.
   2. Expand the current server, right-click the SMTP Virtual Server, and then select Properties.
   3. On the General tab, select Advanced > Add.
   4. In the IP Address box, specify the address of the server that’s hosting the SMTP server.
   5. In the Port box, enter 587 and select OK.
   6. On the Access tab, do the following:
      1. Select Authentication and make sure that Anonymous Access is selected.
      2. Select Connection > Only the List Below, and then specify the IP addresses of the devices that will be connecting to the SMTP server, such as printers.
      3. Select Relay > Only the List Below, and then specify the IP address of the devices relaying through this SMTP server
   7. On the Delivery tab, select Outbound Security, and then do the following:
      1. Select Basic Authentication.
      2. Enter the credentials of the Office 365 user who you want to use to relay SMTP mail.
      3. Select TLS Encryption.
      4. Select Outbound Connections, and in the TCP Port box, enter 587 and select OK.
      5. Select Advanced and specify SMTP.office365.com as the Smart Host.
4. Restart the IIS service and the SMTP service.

After creating the required setting for the IIS SMTP relay, we will need to solve the additional issue that can describe as Enable the IIS SMTP relay to send mail on behalf another Email address.

For that u can create security group in office 365 and give Group delegation as the name of the account you used at authentication ( bold line). 

Please refer : http://o365info.com/smtp-relay-in-office-365-environment/

To remove protection that prevents an OU from accidental deletion

1. Log on to the computer as a member of the Domain Admins group.
2. Open Active Directory Users and Computers.
3. Click View, and then click Advanced Features.
4. First, clear permissions on the OU for which you want to remove protection. To do this, right-click the OU, and then click Properties.
5. In OU Properties, click the Security tab, and then click Advanced.
6. In Permission Entries, select the Deny entry for the Everyone group, and then click Remove.
7. Click OK to close the Advanced Security Settings, and then click OK to close OU Properties.
8. Second, clear permissions on the parent container of the OU for which you want to remove protection. To do this, right-click the parent container, and then clickProperties.
9. In ContainerProperties, click the Security tab.
10. In Group or user names, select the Everyone group, and then clear the Deny check box for Delete All Child Objects, and then click OK to close Container Properties.

DHCP - Event ID 1046 - Authorized issue.

To resolve this issue, follow these steps:

1. Start the Active Directory Service Interfaces (ADSI) Edit MMC snap-in. To do this, follow these steps:
   1. Click Start, click Run, type Adsiedit.msc, and then click OK.
   2. Click Tools, and then click ADSI Edit.
2. In the console tree, expand the Configuration container, expand CN=Configuration, expand CN=Services, and then expand CN=NetServices.
3. In the details pane, you may find objects that resemble the following:
   CNF:<GUID>,CN=NetServices,CN=Services,CN=Configuration, domain
4. Right-click the objects, and then click Delete.
5. Exit the ADSI Edit MMC snap-in.

Verify that the DHCP server becomes authorized after active directory replication is complete.

Force Active Directory replication on a domain controller

In order to force Active Directory replication, issue the command ‘repadmin /syncall /AeD’ on the domain controller.  Run this command on the domain controller in which you wish to update the Active Directory database for.  For example if DC2 is out of Sync, run the command on DC2.

A = All Partitions
e = Enterprise (Cross Site)
D = Identify servers by distinguished name in messages. 

By default this does a pull replication - which is how AD works by default.  If you want to do a push replication use the following command:

repadmin /syncall /APeD

P = Push

You want to do a push replication if you make changes on a DC and you want to replicate those changes to all other DC's.  For example, you make a change on DC1 and you want all other changes to get that change instantly, run repadmin /syncall /APeD on DC1.

For view the replication status 

repadmin /showrepl
repadmin /showrepl <dcname>

repadmin /showrepl * /csv >showrepl.csv