LaTeX error for using "\Box"

Problem: Usage of "\Box" command gives error in LaTeX2e.

Solution: Add "\usepackage{latexsym}" after \documentclass.

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TeXnicCenter Error

Problem: TeXnicCenter gives the error " [DocOpen("%bm.pdf")][FileOpen("%bm.pdf")] " while trying to view the file as pdf.

Solution: The path to adobe reader (.exe) file is incorrect. This occurs mostly because Adobe Reader has been updated to a newer version. Check the path in the TexnicCenter Profiles.

Press Alt+F7, select LaTeX=>PDF (and LaTeX=>PS=>PDF) then on Viewer tab and make sure that Path of executable is pointing to the correct path for Adobe Reader executable.

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