I installed latexdiff to track changes. The first question is where to give the command (latexdiff old.tex new.tex > diff.tex). I saw on the internet that it can be done in the Command/DOS environment. But then I get the error that the file new.tex cannot be found in the directory. I have checked where the other packages are located which is downloaded and which are working. And I have downloaded Perl. What am I doing wrong?
You seem to miss the
new.tex file in your current directory. You can easily check whether it's present by running
dir at the command line, and see whether the file appears in the output. You can always specify the full path to it, if necessary.
latexdiff is installed correctly and on your path (Perl as well), otherwise it would complain either about unknown command, or missing Perl interpreter.
A somewhat tangential note: Version control is almost mandatory if you're serious about using LaTeX for your writings.