One fix is to open the epubcheck.bat file in a text editor like notepad and then change the > to 2>.
This will send the errors to the file instead of the progress messages.
Another way to fix this is to leave > going to errors.txt as it does now and add 2>&1 at the end of the line to redirect the errors to the same file. This way, both progress messages and error messages will end up in the file.
Which you do depends on what you want to happen.
Last edited by DaleDe; 01-07-2013 at 10:24 PM.