In place upgrade from Lync 2013 to Skype for Business 2015

Prerequisites :- Please note that, this article is based on Lync 2013 Enterprise version upgrade on Windows 2008 R2 SP1. If you are using Lync 2013 on Windows 2012 then steps may be different.
1. Make sure that you have the latest CU installed on Lync 2013
2. Update SQL Express edition on all FE servers to SQL 2012 SP2, you can follow the article http://ucserver.blogspot.in/2015/07/update-sql-express-2012-with-service.html
3. Download and install 'KB2533623' https://support.microsoft.com/en-us/kb/2533623
4. Make sure you are using PowerShell version 6.2.9200.0 or later – if not then please download and install latest one.

Publish Topology
1. Install Skype for business Binaries and admin tools on a member server
2. Download corrupt topology from the the member server by using S4B topology builder
3. Right click on the pool which you want to do in place upgrade and choose ‘Upgrade to Skype for Business Server 2015..”

4. Click on ‘yes’

5. You can se the pool is been disappeared from Lync 2013 section

6. Make sure that the pool is visible under Skype section

7. Click on next
.
8. Next to continue..

9. Wait..

10. Review the log and click on ‘Finish’ once done.

Run upgrade on servers
1. Make sure that Lync services are in stopped state on FE servers in the pool where you are going do the update Run ‘Stop-CswindowsService’ all servers in the pool to stop the service

2. Mount the media and launch installation

3. You can see C++ 2013 is getting installed..

4. Select ‘Don’t check for updates right now’ [if you are running offline] and click on next

5. Accept the agreement and click on OK

6. You case the installation started, sit back and wait J it may take lot of time..

7. It may prompt for restarts, if it prompts then reboot by clicking on OK

8. Once the installation is done you can see green tick marks J. Click on OK to finish

9. It will remind you that you have to start the pool after installation, click on OK

10. Execute the installation on all other servers in the pool
11. Once the update is done on all servers then run ‘Start-CsPool –PoolFqdn <pool name>’ command on a FE server and make sure that the services are up on all servers.


Please note that ‘Start-CsPool’ new command introduced in S4B 2015 and by running this command you can start services on all servers in this pool.