Please help: I upgraded to 2014 SP2 and now cannot open native .docx files anymore

Question

As it became impossible to add terms to my MT from Trados (Java security would not allow it anymore), yesterday I finally found a good moment to update my Studio 2014 to SP2 (both Trados and Multiterm). 
 Then a new project arrived: a small docx file. I tried to open it as a single file and, after selecting TMs etc, I have got the horrible message "Object reference not set to an instance of an object", and the file would not open in Studio. However, rtf and doc open normally, as well as docx saved from Word 2003. 
 I have tried to manually install the Cumulative update 8 (KB #5375) and rebooted. No improvement. 
 Environment: Win 7, Office 2003 with Compatibility Pack, Trados Studio 11.2.4364.8 with Autoupdate activated - i3 Processor, 8 GB RAM, SSD. 
 NB1 Before upgrading to SP2, I was working in 2014 with lots of docx files without any problem. NB2 The same docx files, that are impossible to open in Studio 2014 SP2, open normally in my Word 2003. 
 Can somebody help?

Paul · Accepted Answer

Hi Luca, 
 If I open your DOCX in 2014 (or 2011 so it's not an SP2 thing) then I get the Obj Ref Error. If I save it as a DOCX and try again then it works fine. So I opened the file in Word using the "Open and repair" mode and then Word reports this: 
 
 So possibly the problem is associated with this error in the DOCX which Word can live with, but Studio cannot. I'll discuss this with the team here and see whether it's an error we can address in the software as part of a future release, but I'm pretty sure this is not anything to do with SP2. The workaround in the meantime is to simply repair the Word file.

Paul · Answer

Thanks Lena, 
 
I think one problem is that the Object Reference error can be caused by a number of things and whilst one solution might be good for several issues that doesn't mean it will fix them all, nor that we can fix it so easily. We have to find the source of the problem as we can't apply a workaround that might lose information in the file by downgrading it, or deleting Studio setting files. 
 
In this case the style was the problem, and the development team have confirmed that the cause was actually a localised style name. So we can fix this particular issue in a future release. 
 
The object reference error is one of the hardest to nail down because it really could be coming from annywhere. In this case it was triggerred by an unexpected change to the underlying styles. Even Word repaired itself when it found this issue. But it's easier for Word to do this because this is the originating application. 
 
On a side note, you can use more features when you post if you select the "Use rich formatting" option underneath the editing pane. Then you can get your links to be live so they are easier for others to use. I edited your post but this might be helpful for the next time.

Trados Studio > 1. Trados Studio

Please help: I upgraded to 2014 SP2 and now cannot open native .docx files anymore