I added path.sty as a package to the LaTeX preamble a while back, so that the file path to each problem (which appears in instructor copies) would format more nicely. It looks like your LaTeX distribution does not have path.sty. Do you have access to the server? Perhaps:
tlmgr install path
would address this, assuming your LaTeX distribution is TeXLive.
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Generating Hardcopy (TeX-PDF conversionerror)
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