I have Ubuntu 10.04 and I have installed Tex Live 2011 (as super user) as per quick install guide. I also have run the command sudo texhash.

I use Texworks to make PDFs. But I get error when trying to load most basic font packages, like helvet or times. I use this command in the pre-amble of the tex document:

\usepackage[T1]{fontenc}
\usepackage{times}

or any other name for font, like helvet or cmbright.

I get the error that the sty package cannot be loaded:

This is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009/Debian)
entering extended mode
(./letterToPresident.tex
LaTeX2e <2009/09/24>
Babel <v3.8l> and hyphenation patterns for english, usenglishmax, dumylang, noh
(/usr/share/texmf-texlive/tex/latex/base/article.cls
Document Class: article 2007/10/19 v1.4h Standard LaTeX document class
(/usr/share/texmf-texlive/tex/latex/base/size11.clo))
(/usr/share/texmf-texlive/tex/latex/base/fontenc.sty
(/usr/share/texmf-texlive/tex/latex/base/t1enc.def))

Type X to quit or <RETURN> to proceed,
or enter new name. (Default extension: sty)

Is there any way to get a list of font packages THAT CAN BE LOADED using \usepackage command?

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You seem to have a very basic TeX installation. Check with the package manager or do the big step and install TeX Live 2011 –  egreg Oct 18 '11 at 22:49
Your log shows that TeXworks is picking up TeX Live 2009, installed by its package manager. Try running tex -v from the Terminal to see which TeX is being picked up, and if this is correct check your TeXworks preferences to make sure it's using the correct one. –  Joseph Wright Oct 19 '11 at 9:03

Thanks egreg and Joseph.

Apparently I forgot to add the Tex Live 2011 bin directory to the environment variable \$PATH:

PATH=/usr/local/texlive/2011/bin/i386-linux:\$PATH

As a one-time fix it can be directly typed in the terminal. But it would be required again after every reboot (complained about here: Linux forgets TeXlive2011 paths upon restart).

A permanent solution that automatically updates the path accordingly is shown here: Setting the path to textlive installation, round 2

Now everything works!

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