Ensure that Exchange 2010 Update Rollup 1 is installed on the Exchange 2010 server. This package is available here - http://www.microsoft.com/downloads/details.aspx?FamilyID=371add31-d7a0-4...

Create a domain user account called BesAdmin

On the Exchange server, in the Active Directory Users and Computers console, create a domain user called "BesAdmin" and assign it an Exchange mailbox. Set the user account password to never expire.

Send an email to the BesAdmin user to initialise the Exchange mailbox.

Assign the BesAdmin user local administrative rights

On the server that is to host the BES, make the BesAdmin domain user a member of the local administrator group. NOTE - the BES server will first need to have been added to the Domain if not done already.
To do this, on the BES Express server, right click on the icon for My Computer and select Manage. Browse to Local Users and Groups --> Groups --> Administrators and add the BesAdmin user:

Assign the BesAdmin user "log on as a service" rights

On the BES server, also assign the BesAdmin domain user account "log on as a service" rights. To do this, select Administrative Tools --> Local Security Policy --> User Rights Assignment --> Log on as a service and add the BesAdmin user:

Assign "Receive As" and "Administer Information Store" rights to the BesAdmin user

On the Exchange server, launch the Exchange PowerShell and issue the following command:

Get-MailboxDatabase | Add-ADPermission -User "BesAdmin" -AccessRights
 ExtendedRight -ExtendedRights Receive-As, ms-Exch-Store-Admin

Assign Exchange View-Only Administrator rights to the BesAdmin user

Still within the Exchange PowerShell, now issue the following command:

Add -RoleGroupMember "View-Only Organization Management" -Member "BesAdmin"

Assign "Send As" rights on the domain to the BesAdmin user

Within the Active Directory Users and Computers console, open the View menu and select the option to display Advanced Features.

Right click on the domain and select Properties. Click on the Security tab:

Click on the Advanced button:

Click on Add and type in the name of the BesAdmin user:

Select the option to Apply Onto User Objects.
Scroll down to the bottom and tick the option to enable Send As rights:

For good measure, also enable Send As rights on the Exchange server itself within the Exchange PowerShell. Launch the console and issue the following command:

Add-ADPermission -InheritedObjectType User -InheritanceType Descendents -ExtendedRights
Send-As -User "BesAdmin" -Identity "CN=Users,DC=domain,DC=com"

(where "domain" and "com" should be substituted for your specific domain details, eg: DC=brightpoint,DC=co,DC=uk and so on)

To force all of the above changes to take effect on the domain, it may be worth running a group policy update. On the Exchange server click Start --> Run and issue the command "gpupdate /force"

Turn off Exchange 2010 Client Throttling

Exchange 2010 uses client throttling by default to protect the Exchange server from excessive user demands. RIM recommend turning off this feature as it can have an adverse affect on the performance of the BES solution. This is done within the Exchange PowerShell console.
Launch the console and issue the following command to get the "Identity" of the default throttling policy"

Get-ThrottlingPolicy | Where-Object {$_.IsDefault -eq "True"} | FL Identity

the Identity will be displayed:

Now issue the following command:

Set-ThrottlingPolicy -RCAMaxConcurrency $null

You will be prompted to enter the Identity to apply the policy to, enter the result returned above:

Increase the maximum number of connections to the Exchange Address Book Service

On the Exchange Server (or specifically the Client Access Server in a multi-box deployment), browse to C:\Program Files\Microsoft\Exchange Server\V14\Bin and locate the file "microsoft.exchange.addressbook.service.exe.config" and open it in NotePad:

Locate the line "MaxSessionsPerUser":

Increase the value to 100000. Save the file then restart the Address Book Service:

Install the Exchange MAPI CDO 1.2.1 package

The Microsoft Exchange MAPI CDO 1.2.1 package must be installed to provide the BesAdmin user a MAPI connection to Exchange mailboxes as well as access to calendaring information. This package is available for download from our FTP site HERE (Exchange 2010 only).

Run the installer and accept the license agreement:

Now you're ready to install the BES software.