re ;Has MS Windows 10 changed the way files are opened? Yes :) Something to do with sandboxing applications, which prevents them being run from another application. But they did provide a means of getting it to work. So instead of selecting the app yo desire, select the really obvious Action name TWINUI.

Tools > Options > Attachments > Incoming tab or Menu icon > Options > Options > Attachments > Incoming tab

If Microsoft Word document is listed in the 'Content Type' column: click on the 'Action' to see a drop down list. select : 'Use Other' a 'Select Helper Application' window opens. Look for and select TWINUI. This refers to the windows 10 shell and chooses the system default application for the file type. click on OK Click on OK to close and save Options.

If Microsoft Word document is NOT listed in the 'Content Type' column:

Select email so you see attached document. right click on attachment and choose to 'Open With'. Select 'Other'. a 'Select Helper Application' window opens. Look for and select TWINUI. click on OK

select 'Do this automatically for files like this from now on' click on OK

This will list it in the Options > Attachments > incoming.

Hi Alan-vancouver Did the information work for you?

If yes, can you select my relevant comment as 'Chosen Solution'. This would close this question and offer good feedback for everyone who sees this.

Dear Toad-Hall, Thanks but TWINUI is not on the list of options.

I cannot open word.docx files but word.doc files are ok.

Alan

What version of MS Office Word are you using ? 2003, 2007. etc ?

Please post image of the following; Tools > Options > Attachments > incoming or Menu icon > Options > Options > Attachments > incoming

make sure anything regarding MS Office Word is visible.

Hi.

I have Word 2003 and 2007 installed. The APPs show both these version installed.

Tools>Options>Attachments>Incoming only displays: 'application/msword:.doc' but not .docx

How can I add .docx to this list?/

Thanks,

Alan

I've just tested two ways of setting this up. Bare in mind i'm using Vista OS and Office2007. So I would recommend you try the first option, but there is no harm in trying the second option as you will be able to swap it easilly afterwards.

• Right click on attachment .docx and select 'Open'
• Select 'Open With' and choose either of the following:

This is the option I am currently using on Windows Vista with Office 2007. AS you may not know whether the attached .docx has been created using a more recent version of MS Word choose:

• Microsoft Open XML converter(default)

In the past when you were probably only receiving those created in version 2007, then you could have selected: 'Open With' and clicked on 'Use Other' from the drop down and then click on 'Browse' then accessed : C:\Program Files\Microsoft Office\Office12\WINWORD.exe and clicked on 'Open'. This method will still open .docx files on my system, but then I did test it using a document created in version 2007. If you choose this second method and want to change your mind later, then it will be in the Tools> Options> Attachments window and you can select the Action 'Microsoft Open XML converter(default)' to easily change it.

• Select: 'do this automatically for files from now on'
• click on OK

The document should then auto open from now on. It will now show up in the Options Attachment window.

Thanks for the suggestion but I cannot even get to 'Open with'... the error message "application not found" pops up.

How can I add MS Word.docx or Microsoft Open XML converter to the list under the Options>Attachments list??

This is one of many complaints caused by Windows 10; a big mistake installing.

Thanks

Alan

I think this is something to do with Windows 10 and the way it wants to open docx documents that have been downloaded. It will want to open them in Protected view which means it is trying to open in a sandbox environment - hence why I was thinking that the 'TwinUI' option should have worked. It is supoosed to be part of the security features to help protect against virus's/malware that could be in a received document.

Please try the following and then retry to open the document as per method I suggested.

Located some info at these links which suggests this may be the reason for the issue you are experiencing. fuller info here:

• http://techvedic-tech-support.blogspot.co.uk/2013/06/how-to-disable-protected-view-in.html
• https://support.office.com/en-us/article/What-is-Protected-View-d6f09ac7-e6b9-4495-8e43-2bbcdbcb6653

In Word, Excel and/or PowerPoint choose: File-> Options-> Trust Center-> Trust Center Settings…-> Protected View-> deselect options to allow opening of documents.

• Enable Protected View for files originating from the Inter-net • Enable Protected View for files that are located in poten-tially unsafe locations • Enable Protected View for Outlook attachments

Thanks again. I disabled the protected view options but it did not fix the problem. I still get the message "application not found". Is there any way of adding Word 2013 to the Options>Attachments list in Thunderbird?

Alan

re : I have Word 2003 and 2007 installed. The APPs show both these version installed. Then you mention Is there any way of adding Word 2013, Are you now saying you are running three different versions of MSOffice?

Did you reinstall all of these various MS Office apps after upgrading to Windows 10 ? I did come across someone who updated and had a similar problem. In their case, they uninstalled MS Office completely and then reinstalled just the one most recent version and it resolved their issue.

The error message seems to think that it is already in your Attachments list as it is already looking for an application instead of asking what app to use. Q: Did thunderbird open .docx files before upgrading to Win10?

After upgrading to windows10, you reinstalled Thunderbird. Q: Did you copy paste your old profile folder contents into the new profile or did you just start using a new profile because you only have imap mail account?

Please post image of : Tools>Options>Attachments>Incoming window make sure it shows everything in that window, even if this means posting two images to show anything revealed after scrolling.

Perhaps re-installing Word 2013 will work as you suggest.

1. I meant to say Word 2013 and 2007 are installed. 2. Yes both could be opened from emails before Win 10 was installed. 3. No I did not copy any profile.

Can't seem to paste screenshot into this form/forum.

I'll try re-installing Word. Why does Windows 10 add nothing but inconvenience.

Dear Toad-Hall, I ran 'troubleshoot compatibility' in MS Word and it fixed the problem. Thanks for your suggestions.

Alan