[Tex/LaTex] Error: Could not start the command: pdflatex.exe -synctex=1 -interaction=nonstopmode “eigenvector or eigenvalue decompositions”.tex

compilingerrorsmiktexpdftextexstudio

I have a .tex file in the following path

C:\Users\sepideh\Desktop\dissertation\formulasInLatex\eigenvector or
eigenvalue decompositions.tex

with the following content:

\documentclass[a4paper]{article}
\usepackage{amsmath}
\begin{document}
    $
    T_3 = U_P\sum_P U_P^{-1}
    $
\end{document}

when I press the button Build & View in TexStudio
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I get the error:

Error: Could not start the command: pdflatex.exe -synctex=1
-interaction=nonstopmode "eigenvector or eigenvalue decompositions".tex

I also had another file in the same path:

C:\Users\sepideh\Desktop\dissertation\formulasInLatex\wave covariance
matrix.tex

with a PDF file associated to it. That was built almost a year ago with an earlier version of TexStudio (Currently I'm using TeXstudio 2.11.2 with MikTex 2.9)

C:\Users\sepideh\Desktop\dissertation\formulasInLatex\wave covariance
matrix.pdf

Meaning that I'm sure that the syntax of the second file is correct because it was compiled successfully in the past.
But when I deleted the PDF file to compile and build it again, I encounterd the same error:

Error: Could not start the command: pdflatex.exe -synctex=1
-interaction=nonstopmode "wave covariance matrix".tex

Can anyone suggest me why the command pdflatex.exe couldn't start?

Best Answer

In order to solve this problem, I did the following:
From the menus at the top:

Options > Configure TexStudio...

enter image description here
Choose Commands on the left

enter image description here

and then manually enter the paths to .exe files by clicking on the below icon (select program) next to each line and then press OK.

Thanks to the comments made by @JosephWright and @PietvanOostrum .