This just started fairly recently. I enter the password, and Word crashes with no error message. This happens with existing files that have opened fine for years. I can also create a new file, save it with a password, close it, then try to open it, and Word crashes. I have an up-to-date version of Office 365 on Win 10 Home. I have already reinstalled Office, to no avail. For what it's worth, Excel opens passworded files fine (I don't know if Excel and Word share a decryption module). Any ideas will be appreciated.

If you start Word in safe mode is this a problem?
Open Office apps in safe mode on a Windows PC - Microsoft Office

Yes, same behavior in Safe mode.

In that case, try an online office repair. It should take about 30-60 minutes.

Repair an Office application - Office Support

Thanks, but I did that. Both the quick version and then the long (total reinstall). Still have the same problem.

Repair and reinstall are not the same thing. I accept that you have tried both.
Can you try opening one of the documents on a different system?
What happens if you attempt to encrypt a new document? Does it save? Can you open it?


I believe the encryption algorithm is the same for all of Office, but that is merely a belief. I could not cite any authority for it.

I've tried the short repair, which didn't help, and the online repair twice. Both times the online repair failed with the message Something went wrong, with Error Code 30010-4. Both times, that left my system without Office installed, so I reinstalled Office. I still have the same problem.



I can open the encrypted files on my old Win XP, Word 2007 system, and my Android phone, but Word 365 on Win 10 still crashes when I try to open the files.



I can create a new Word file, password protect it, save and close it in 365, but when I try to reopen it, Word 365 still crashes. The other systems will open the new file.

I also see you are responding to a similar issue on the Microsoft Support pages, and tried your sfc /scannow suggestion, but it did not find any integrity violations.

What is your version number in Word 2016? I am on the Insider track and showing 1909.
If you want, password protect a dummy file and post it here with the password. I will try to open it on my Word 2016.
How to include a screenshot in your post - Microsoft Community


Is this the only problem you are having with this installation?


I suspect that the problem is with your Office installation and that a successful repair is needed. You may need to start Windows in safe / networked mode and run the repair from there.

My Word version is 1908. This is the only problem I'm having with the installation (other than the online repair bombing).


I will try the repair from safe mode, but I will have to get an ethernet to usb adapter first -- my laptop doesn't have an ethernet port and safe / networked mode doesn't appear to work over wi-fi.


Thanks for your help -- I'll let you know how/if I get it working.

I finally got it working, but I don't know how. A couple things I learned in the process:
1) Safe Mode with Networking does work over wifi, but you have to click on the Network icon (globe) in the lower right corner and connect to your network before entering your password.
2) MSO Repair would not run in Safe Mode with Networking - it appears that you cannot start MS Click-To-Run service in that mode.

The last thing I did before the problem disappeared was to run MSO Quick Repair with a wired connection to the internet (after a normal windows startup). But I don't believe this was the solution, because the Quick Repair had completed successfully several times with a wifi connection without resolving the problem.


Anyway, thanks again for all your help.

Hi Paul, I have what seems to be the exact same problem (only in word, doc opens correctly on other system). Anyone else have any suggestions as to the fix? I have done the same attempts at fixing the problem but with no success.

Thanks,
Vincent

Version number and operating system?

Hi Charles,
Thanks for responding!
Versions are Microsoft® Word 2019 MSO (16.0.14326.20164) 64-bits; windows 10 pro build: 19043.1202

Thanks for your help,
Vincent

One password-protected document?
More than one password-protected document?
All password-protected documents?


Same thing happens if Word is opened in safe mode?
.doc or .docx formatted documents?

Hi,
Happens to all the pasword protected d0cs on this system; When opening the same passoword protected docs on another system the documents open normally.
Safemode makes no difference.
Format is docx
Any ideas what to do, or should I just reinstall the whole system?

Thanks, Vincent