When I try to compile my paper I get the following error:
! LaTeX Error: Filemathtools.sty' not found.`
Other packages are successfully found and automatically installed, but
mathtools.sty is not. I just reinstalled windows 8.1 and Miktex 2.9 with TeXWorks Version 0.4.5. The paper compiles properly on my other machines.
I have found mathtools.sty online, but adding it manually only results in another style file not being found. What is going on - why is Miktex failing to automagically find mathtools.sty and other style files?
EDIT The problem is that the package manager has somehow "desynchronized" (even though it's a fresh install). To fix it, run Miktex Package Manager as administrator---there should be a version "Package Manager" and a version "Package Manager (Admin)" - run the latter. Go to Repository-->Synchronize. When that completes, close the package manager and your TexWorks should automatically find the needed style files again. If the synchronize fails, then you may not have run the (Admin) version of Package Manager.