Excel 2016

Hi ! First question i may ask: Why is it you get the last message about a ".doc" when it is an Excel Workbook? Next question: Did your company migrate all your files from file server to O365 without asking about the different (thousand) relationships between the most important Workbooks? If so, I would strongly recommend asking your adminstrator to repair your several workbooks connections.

Are you online, when you open your Workbook? Or working offline? Then your connections can´t reach out and this is the main cause. Try it online.

And I ask myself if you had an Office 365 Training before working with your files? Maybe that you are not anymore allowed to open this particular workbook because you are not in the right permission group to work on that file. Or on that other workbooks / Documents, which have been related to your permission level is the wrong one... Thousand workbooks can cause thousand questions and the most relevant one is about your permissions to work on those files.

Did you have a training about Office 365 so far? If not, ask your fellow collegues, if they have the same problems as well. Then its a time to send a request to your HR or your IT to set up Office 365 Trainings, concerning your new dos and donts. Before training request you could do this today: Try to go to the Excel local Application on your PC, without any workbook. Then try to click HOME Tab => Open. In that dialog box pls. click on the small arrow within that "open..."-Button. Take the very last option "Save and Repair...".

Follow the instructions.

If it doesnt open, because there are tooooo many lost relations and VBA Starting codes within, just exit your excel, open your workbook with pressing SHIFT key while you open it. With that shortcut you can temporarily block all VBA Codes running on open event. 

Then - when its opened - go to your HOME Tab again. Check the "Information". In the right bottom corner you ll see, what connections are in your workbook. You have to ask your administrator, if you don't have permission to open the several linked files in there. Send him/her a screenshot of this dialogue. I give you a screenshot here as example.

Hope that helps. Pls give a Like, if it does. Greets, Eva.