I can't open my doc.sdlxliff file in editor.

Hi,

 

I have been working on a project for a while and it was 36% done. I did some new translation this morning and appropriately saved everything. But somehow I couldn't open the file in editor  now. The pop-up message said "Failed to open xxxxx.doc.sdlxliff". Refer to the additional error information below for more details. 

And the error message said, "the file at location xxxxxxx does not exist!" 

 

I have been using SDL for 2 years and it never happened before. I saved the files in Dropbox. What happened? Help. 

 

Thank you very much.