# Error: ! LaTeX Error: File book.cls' not found [closed]

I am using Ubuntu on my laptop.

I am new to using LaTeX. I have recently installed Texmaker and I am writing a dissertation; I downloaded a template somewhere from the internet. It has been working fine. But today, when I tried to compile it into a PDF, I got this error:

! LaTeX Error: File book.cls' not found.


I have looked at other posts, but I have no idea what they meant. Can someone explain to me in layman terms, how can I solve this problem ?

Texmaker said the error is produced in Latex/Classes/PhDthesisPSnPDF.cls line. So I opened the file and this is what I have from line 31 to line 37

%If you want to use a Book style document then uncomment the following 3 lines and comment the above 8 report style lines:
\DeclareOption*{\PassOptionsToClass{\CurrentOption}{book}}
\ProcessOptions\relax
\ifx\pdfoutput\undefined

Does the file book.cls exist in your TeX distribution? It should be at TEXMF/tex/latex/base/book.cls. – ChrisS Aug 28 '13 at 8:41
I just tried cd TEXMF/tex/latex/base/book.cls, the directory TEXMF doesnt seem to exist. How do I find my Tex distribution in ubuntu ? – user1769197 Aug 28 '13 at 8:50
TEXMF is an acronym for the root directory of your TeX distribution. Where exactly the root directory is located varies across TeX distributions. Please post a minimum working example (MWE) that generates the error messages you're encountering. All one can tell is that it looks like you're using the document class contained in ./Latex/Classes/PhDthesisPSnPDF.cls, but it's not clear who this class file then tries to invoke the book document class. – Mico Aug 28 '13 at 8:54