Error message when opening word doc: "Not Implemented" (Word for Windows)

Sounds like your issue is different.  Even with the "Not Implemented" problem that the rest of us have posted, the file can always be opened by starting the application (ie, Word or Excel) and then going to "File" -"Open" and open the existing file.  It is only when double clicking in Windows File Explorer that there is an issue.  Also, if, instead of double clicking, you right click and select "Open with" and then select "Choose Another App", followed by "OK", it should also open the file.

I had/have the same issue. It seems OneDrive does not sync the documents very quickly. And it tries to save to OneDrive when you only want to save it to "this PC". In my case, I was trying to upload a particular document to a website. Every time I tried to open the document from my "documents" folder, I would get the "file not implemented" error message. So, when I had "my documents" opened, I found the file that had not been implemented that I am trying to upload. I right-clicked on the document. from the menu that pops up, I went to "send to". From there, I chose to send the document to "documents". I know, sounds ridiculous- the file is already trying to save in the "documents" folder. However, after I did this, it saved a copy immediately, and I was able to immediately upload it. Hope this helps at least temporarily. I have no idea how to fix it otherwise. I've tried pausing OneDrive syncing temporarily hoping I could just retrieve it from my computer- that didn't work. I also save these documents on "this PC" as well, so I am not sure why it feels the need to try and save it on my OneDrive when that is not what I actually saved it to.  Sounds like an issue a lot of people are having this issue. It would be super cool if Microsoft gave us a good answer.

I've uninstalled Onedrive, and ... happiness and serenity are back again !!!

Stan, I thank you a lot !

May your name be engraved on the pediment of the monument dedicated to the Great Exabyte (aka ol' GEB) !

Same problem here, comes and goes over the past month or so for both Word and Excel.

Same issue for a lot of friends, family and co-workers. No fix other than the "open-with" work-around and hoping it goes away for a while after a reboot.

I just got Windows 10 and Office 365. I was having the same problem, and I finally figured it out. While on the Word Doc, go up to the top left and put autosave on OFF. Then save it, this way you will get the 'save as' option. After doing it this way it was saved so I could access it the way I used to with the older version of Office and had no problem uploading it to another site. Yeah, no more not implemented message.