Cannot Open .DOCX after downloading or other MS Office files

I have just installed OwnCloud version 9.1.4. When i download a word file (.DOCX or .DOC) through the web browser , i am then unable to open it. ( "Word experienced an error trying to open the file. ") n.b. This is not editing in browser, simply downloading the file via http/browser(chrome and IE) I think it is permission related as the files are identical ( when checked with TextPad comparision tool ) . The file will open fine when opening from my local owncloud folder. I am currently using Word 2016.

When i try on a new laptop running Word 2013, i can open the file ( it gives a warning about Protected View and an Enable Editing Button ) . But when i try to save it i get an error "this file is in use by another application or user ( C:\Users\Me\AppData... \Normal.dotm)

This also happens with .xlsx files ( and id guess other Microsoft Office based files )

Anyone else experiencing this or have any ideas on what is happening.

Kind Regards

Cormac