3.04 and opening docx files -bug?

[credneb]

Ever since upgrading to 3.04 I have been unable to open .docx files in Japanese in NWP. (Have not tried English bc I don't have any) The following error is reported.

I have tried opening files from a year or more ago that the previous version had to problem opening.
If I open the file in Word and save as a .doc file, 3.04 opens it with no problem.
If I tell NWP to Retry, the file opens.
These are not complex files. They only contain text with no extraordinary formatting.
Is this a known problem? (Have not seen it reported here)

Using OSX 10.11.6.

I can send a redacted file if desired.