If the file has been analysed successfully but contains zero words, this is likely a result of cleaning options being selected during the upload process.
To remedy this, simply re-upload the file being sure to disable all the cleaning options.
If you have done this, and are still getting zero words, then you may be using the incorrect upload format. Check to make sure you have selected the correct source type and that you haven’t done any manual manipulation to the data.
If this still does not fix the problem then it may be the case that the content column, typically labelled “text”, is missing from the upload. Check the upload file to ensure that the content column is present and labelled correctly.