If you write lots of Exchange scripts (as I do), and have several different versions of Exchange on which you need to run those scripts (as I do); you soon see the need for being able to determine what version of Exchange a particular server is running – and you may need to do this outside of the Exchange Management Shell.
This may be necessary because of different behaviors that are required with the Exchange Management Shell depending on the version of Exchange. It also may be required because the version of Exchange pre-dates the Exchange Management Shell (i.e., Exchange 2003). As an additional rationale, your script may need to load the Exchange Management Shell and cannot do that properly without knowing the version of Exchange that is being targeted (the process differs between Exchange 2007 and Exchange 2010).
Thus, I've written a couple of functions that I wrap in a script to give me that information. Get-ExchangeServer, the function, returns a simple object containing the name of the server examined, plus the version of Exchange that is running on that server. That is:
struct result {
string Name;
string Version;
}
If the result of the function is $null, then the version could not be determined and the server targeted either does not exist or is (very likely) not running Exchange. If the server does not exist (or the firewall on the server prevents remote management via WMI) then an error is displayed.
The version information about Exchange is stored in the registry of each Exchange server. The script below shows some techniques for accessing the registry to obtain string (reg_sz) and short integer (reg_dword) values while using PowerShell. Note that PowerShell has multiple mechanisms for accessing this information, including the so-called Registry Provider. I personally find using the WMI functions to be a bit easier to handle.
You can include these functions directly into your PowerShell profile, or you can dot-source the function on an as-needed basis.
Without further ado, enjoy!
###
### Get-ExchangeVersion
###
### Return the version of the specified Exchange server
###
Set-StrictMode -Version 2.0
$HKCR = 2147483648
$HKCU = 2147483649
$HKLM = 2147483650
function RegRead
{
Param(
[string]$computer,
[int64] $hive,
[string]$keyName,
[string]$valueName,
[ref] $value,
[string]$type = 'reg_sz'
)
try {
$wmi = [wmiclass]"\\$computer\root\default:StdRegProv"
if( $wmi -eq $null )
{
return 1
}
}
catch {
##$error[0]
write-error "Could not open WMI access to $computer"
return 1
}
switch ( $type )
{
'reg_sz'
{
$r = $wmi.GetStringValue( $hive, $keyName, $valueName )
$value.Value = $r.sValue
}
'reg_dword'
{
$r = $wmi.GetDWORDValue( $hive, $keyName, $valueName )
$value.Value = $r.uValue
}
default
{
write-error "Unsupported type: $type"
}
}
$wmi = $null
return $r.ReturnValue
}
function Get-ExchangeVersion
{
Param(
[string]$computer = '.'
)
if( $computer -eq '.' )
{
$computer = $env:ComputerName
}
## Exchange vNext (assumption!)
## HKLM\Software\Microsoft\ExchangeServer\v15\Setup
## MsiProductMajor (DWORD 15)
## Exchange 2010
## HKLM\Software\Microsoft\ExchangeServer\v14\Setup
## MsiProductMajor (DWORD 14)
## Exchange 2007
## HKLM\SOFTWARE\Microsoft\Exchange\Setup
## MsiProductMajor (DWORD 8)
## Exchange 2003
## HKLM\SOFTWARE\Microsoft\Exchange\Setup
## Services Version (DWORD 65)
$v = 0
$i = RegRead $computer $HKLM 'Software\Microsoft\ExchangeServer\v15\Setup' 'MsiProductMajor' ( [ref] $v ) 'reg_dword'
if( ( $i -eq 0 ) -and ( $v -eq 15 ) )
{
$obj = "" | Select Name, Version
$obj.Name = $computer
$obj.Version = 'vNext'
return $obj
}
$i = RegRead $computer $HKLM 'Software\Microsoft\ExchangeServer\v14\Setup' 'MsiProductMajor' ( [ref] $v ) 'reg_dword'
if( ( $i -eq 0 ) -and ( $v -eq 14 ) )
{
$obj = "" | Select Name, Version
$obj.Name = $computer
$obj.Version = '2010'
return $obj
}
$i = RegRead $computer $HKLM 'Software\Microsoft\Exchange\Setup' 'MsiProductMajor' ( [ref] $v ) 'reg_dword'
if( ( $i -eq 0 ) -and ( $v -eq 8 ) )
{
$obj = "" | Select Name, Version
$obj.Name = $computer
$obj.Version = '2007'
return $obj
}
$i = RegRead $computer $HKLM 'Software\Microsoft\Exchange\Setup' 'Services Version' ( [ref] $v ) 'reg_dword'
if( ( $i -eq 0 ) -and ( $v -eq 65 ) )
{
$obj = "" | Select Name, Version
$obj.Name = $computer
$obj.Version = '2003'
return $obj
}
### almost certainly not an Exchange server
return $null
}