To many of us, submitting a disavow link file to Google for their consideration should be done in CSV or text format. Most of us wouldn't consider using an excel file or Word document. But that is not always the case.
A Google Webmaster Help thread has a web site owner who submitted a Microsoft Word document in the file format .DOCX via the disavow tool upload form. Then they complained that nothing happened in the forum. Google's John Mueller explained that the file format he used was not supported. John wrote:
After reviewing the situation with your site, it appears that the unnatural links to your site were not really disavowed.. Looking into the details, the file you uploaded to the disavow tool appears to be a "DOCX" file, and not a normal text or CSV file. Because of that, we don't have much that we can process there. To our systems, these lines look mostly like gibberish, so while we try to use them for the tool, they don't map to the URLs that you probably wanted to submit.
I'd recommend submitting it again, in the proper format, so that it can be processed and used for the reconsideration request. As I don't know for sure that your file would contain all of the relevant unnatural links, a proper submission would definitely help. A good way to double-check that we're able to pick up the content is to use the "download" link after submitting, and to view it in Google Docs instead of downloading it as a CSV file.
So make sure to stick with a CSV or text file for this for now.
Forum discussion at Google Webmaster Help.