According to the Technet documentation you should be able to install Exchange 2010 in an environment where Exchange 2007 is running. A while ago I got a question from a customer who had an issue when trying to install Exchange 2010. The problem occured running the setup.com /ps to extend the schema for Exchange, the following error message was displayed:
The schema version of Exchange 2007 SP3 is higher than the one from the Exchange 2010 setup. This makes it impossible to install Exchange 2010.
When you have installed Exchange SP3 you will have to wait for a service pack which will extend the schema. Because a lot of people will probably install Exchange 2007 SP3 this may be included in SP1 for Exchange 2010.
Below an overview of the Exchange versions and which schema version they use:
| Exchange | Schema |
|---|---|
| Exchange 2000 RTM | 4397 |
| Exchange 2000 SP3 | 4397 |
| Exchange 2003 RTM | 6870 |
| Exchange 2003 SP3 | 6936 |
| Exchange 2007 RTM | 10628 |
| Exchange 2007 SP3 | 14625 |
| Exchange 2010 | 14622 |
If you would like to know how you can find out which version of AD schema you are using then take a look at the site below:
Rubrieken: Exchange 2010 ~ Trackback
30 July, 2010 op %I:%M %p
I’ve just done this in a lab environment and did not reproduce the error above. New install (no Exchange in forest at all) > 2007SP3 DVD – PrepareAD switch > Exchange 2010 RTM DVD – PrepareAD switch.
After 2007SP3 PrepareAD the rangeUpper value of ms-Exch-Schema-Version-Pt was 14625 and after 2010 RTM PrepareAD it was the same.
30 July, 2010 op %I:%M %p
Brain,
Yes I know that will work, but the question is is it really supported since you will skip an Exchange schema prep for Exchange 2010. At this moment Microsoft is investigating the issue and as soon as I have an official answer from them I will let you know.
Regards,
Johan
31 July, 2010 op %I:%M %p
There’s no such thing as Exchange 2003 SP3 .. is there?
FYI, Forest Schema version Exchange 2003 SP2 is still 6870 ..
31 July, 2010 op %I:%M %p
Ehm, scrap that, 6936 is ok. Gets set after actually installing Exchange 2003 SP2, not after forestprep/domainprep using exchange 2003 sp2.
(had to do an install of these so I thought I’d verify those numbers while I’m at it)
31 July, 2010 op %I:%M %p
It’s late
mixed things up .. the numbers
dsquery * “CN=ms-Exch-Schema-Version-Pt,CN=Schema,CN=Configuration,DC=la
b,DC=local” -scope base -attr rangeUpper
rangeUpper
6870
dsquery * “CN=LabOrg,CN=Microsoft Exchange,CN=Services,CN=Configuration,
DC=lab,DC=local” -scope base -attr objectVersion
objectVersion
6903
dsquery * “CN=Microsoft Exchange System Objects,DC=lab,DC=local” -scope
base -attr objectVersion
objectVersion
6936
20 August, 2010 op %I:%M %p
Does anyone know how to install Exch. 2010 then?
Because I have already installed the Exch. 2007 SP3 on the same domain
20 August, 2010 op %I:%M %p
Hugo,
Just run the setup via the GUI this should work, it only goes wrong when performing the schema, forest and domain prep will be done manually by using the setup.com /ps etc. parameters.
Regards,
Johan