SharePoint Cumulative Update slipstreaming and language pack

Question

I'm slip-streaming service pack 1 of SharePoint in both server setup and language pack setup (in the update folder). It is the correct way because the updates are language targeting (sp1 EN for the server install, and SP1 language pack FR for the FR language pack, and so on).

June 2011 Cumulative update is, in opposition, not targeted to a specific language. (xxx-glb.exe for global).

I slipstreamed this install into the update folder of the server install, do I have to do it also for language packs ?

To resume, is this file layout ok (order of installation) ? :

1. \SharePoint server EN
   • \everything else from the installation media
   • \updates
     • SP1 for server
     • CU for server
2. \Office Web apps EN
   • \everything else
   • \updates
     • SP1 for office web apps
     • CU for OWA
3. \SharePoint Language pack FR
   • \everything else
   • \updates
     • SP1 for language pack FR
     • all CU (server and OWA)

Answer 1

When slip streaming, ALL (SP, CU) your updates go into the updates folder in the installation source of your application. The language packs go into the language updates folder. When you install from the source, everything in the updates folder gets processed.

Here is post by Ron Grzywacz on MSDN regarding this topic Service packs and LP slip-streaming. http://blogs.msdn.com/b/ronalg/archive/2011/07/11/slipstream-sharepoint-2010-sp1-and-language-packs-w-sp1-into-rtm.aspx

When dealing with language packs, it is probably NOT a good idea to slip stream the CU's because of how SharePoint processes the updates. If you slipstream LP and the CU's what happens is SharePoint will install the server updates first (the service packs and the CU's), then apply the language packs. CU's contain BOTH the general and localized files for ALL languages. So because the CU's are applied before the LP, your LP files will not get updated with the CU bits unless you installed the CU again.

So I would slipstream the Service Pack(s) and the language packs, but not the CU's. Apply the CU's after you have installed from your slip-streamed source so ALL of the applicable files will be updated correctly.