Failed Lync Server 2013 Prerequisites on Server 2012/2012 R2

This issue has caused me grief on several servers this week and I finally figured it out... so now you benefit.

If you wait to install your Prerequisites after you run Windows Update on Server 2012/2012 R2 you will get an error

I really doesn't matter what you specify as you "Source" the Prerequisites Powershell command we all love will fail.

So if you do searches you will come across others having this issue. They solved it by running.

     dism /online /enable-feature /featurename:NetFX3 /all /Source:d:\sources\sxs /LimitAccess

Which would help... but there is one last key piece of information I'll give you... which is the point of this blog because I found the answer in a comment on an obscure blog post.

If KB2966827 or its brother KB2966828 are installed the dism command will fail to install about 67% of the way in.

Not surprisingly the work around is to uninstall either of those two KBs... or to do your Prerequisites before you run Windows Update.

Update: Couple of things, Microsoft provided another update KB3005628 that will supposedly go in and take care of the issue, so you don't have to uninstall the above KBs. 

However, I never got around to testing it because it seems like as of now, a fully patched 2012 R2 box only needs the dism command above executed against a mounted ISO (or burned DVD). IT WILL NOT WORK pointed to c:\Windows\WinSXS directory. I do not know if this is the case with Server 2012 (R1). But hopefully there is enough in this blog post for you to work through it if you find yourself in that predicament.

There you go... my pain is your gain. Enjoy.