The comments above suggest that there may be a way to solve your problem without learning how to manually install LaTeX packages. But, it's not a bad idea to know how for troubleshooting, and quick fixes.
- create a TDS directory structure (once)
- place mathtools directory inside (most packages should go in
.dtx files (creating
- (I think I've more often seen
latex <some package>.ins)
- (Optional) further cleanup towards TDS conventions
You'll want to create a
texmf directory. Determining where to put it, that is, the default location, in Windows, is discussed here: packages - Where is texmf on a Windows install - TeX - LaTeX Stack Exchange.
So in your explorer, you'll want to head to your home directory, and create directories until you have the following chain:
c:\Users\<your user name>\texmf\tex\latex\
You would put the
mathtools directory there, so that you have for instance
c:\Users\<your user name>\texmf\tex\latex\mathtools\mathtools.dtx
Now, open up a command prompt, and
cd (change directory) to this location, that is,
cd c:\Users\<your user name>\texmf\tex\latex\mathtools\
From there, run
tex on the appropriate files, that is, type
You may also need
This will create the style files,
This is enough. Latex may now know where to find the style files because of TDS (TeX directory structure). If it does not, you many have to run
texhash or similar.
You could follow convention further, cleaning up, putting the documentation (pdfs) into
texmf\doc\mathtools\, and put the
.dtx (and sometimes
.ins) files into some source directory for easy access if you want to recover them later (without internet?).