Opening Office files slow over network
This is a weird one, we have a teacher who opens up an excel spreadsheet and then gets his class to open it as well. This worked fine on server 2008r2, but since upgrading to server 2012 r2 things have gone massively slow. It can take 5 minutes for the document to open up. It does seem quicker if the teacher closes the document first before kids open it, but that isn't an acceptable solution. Has anyone else come across similar problems on 2012 r2?
Also could this be a data de duplication issue?
Any ideas on how to troubleshoot and fix this will be appreciated. If I open the file when the teacher has it open it takes ages, and will give me the this file is locked, and allow me to open a read only copy.