LaTeX Error: Can be used only in preamble
This error appears when you have included a package or class in the main body of your document, instead of in the preamble. The preamble to the document consists of everything written before \begin . In the preamble you define the type of document you are writing, the language and several other elements. For instance, a normal document preamble would look like this:
\documentclass[12pt, letterpaper]article> \usepackage[utf8]inputenc> \usepackageamsmath> \titleFirst document> \authorHubert Farnsworth \thanksfunded by the ShareLaTeX team>> \dateFebruary 2014>
If you write \usepackage in the main body of the document (after \begin ) instead of in the preamble, you will generate the error message shown below.
LaTeX Error: Can be used only in preamble.
See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. . l.4 \usepackage Your command was ignored. Type I to replace it with another command, or to continue without it. [1
To fix this error, make sure that all \usepackage commands, as well as \documentclass[. ] , are written before \begin . To learn more about how to structure a document in L a T e X , check out our documentation.
- Documentation Home
- Learn LaTeX in 30 minutes
Overleaf guides
- Creating a document in Overleaf
- Uploading a project
- Copying a project
- Creating a project from a template
- Using the Overleaf project menu
- Including images in Overleaf
- Exporting your work from Overleaf
- Working offline in Overleaf
- Using Track Changes in Overleaf
- Using bibliographies in Overleaf
- Sharing your work with others
- Using the History feature
- Debugging Compilation timeout errors
- How-to guides
- Guide to Overleaf’s premium features
LaTeX Basics
- Creating your first LaTeX document
- Choosing a LaTeX Compiler
- Paragraphs and new lines
- Bold, italics and underlining
- Lists
- Errors
Mathematics
- Mathematical expressions
- Subscripts and superscripts
- Brackets and Parentheses
- Matrices
- Fractions and Binomials
- Aligning equations
- Operators
- Spacing in math mode
- Integrals, sums and limits
- Display style in math mode
- List of Greek letters and math symbols
- Mathematical fonts
- Using the Symbol Palette in Overleaf
Figures and tables
- Inserting Images
- Tables
- Positioning Images and Tables
- Lists of Tables and Figures
- Drawing Diagrams Directly in LaTeX
- TikZ package
References and Citations
- Bibliography management with bibtex
- Bibliography management with natbib
- Bibliography management with biblatex
- Bibtex bibliography styles
- Natbib bibliography styles
- Natbib citation styles
- Biblatex bibliography styles
- Biblatex citation styles
Languages
- Multilingual typesetting on Overleaf using polyglossia and fontspec
- Multilingual typesetting on Overleaf using babel and fontspec
- International language support
- Quotations and quotation marks
- Arabic
- Chinese
- French
- German
- Greek
- Italian
- Japanese
- Korean
- Portuguese
- Russian
- Spanish
Document structure
- Sections and chapters
- Table of contents
- Cross referencing sections, equations and floats
- Indices
- Glossaries
- Nomenclatures
- Management in a large project
- Multi-file LaTeX projects
- Hyperlinks
Formatting
- Lengths in L a T e X
- Headers and footers
- Page numbering
- Paragraph formatting
- Line breaks and blank spaces
- Text alignment
- Page size and margins
- Single sided and double sided documents
- Multiple columns
- Counters
- Code listing
- Code Highlighting with minted
- Using colours in LaTeX
- Footnotes
- Margin notes
Fonts
- Font sizes, families, and styles
- Font typefaces
- Supporting modern fonts with X Ǝ L a T e X
Presentations
Commands
Field specific
- Theorems and proofs
- Chemistry formulae
- Feynman diagrams
- Molecular orbital diagrams
- Chess notation
- Knitting patterns
- CircuiTikz package
- Pgfplots package
- Typesetting exams in LaTeX
- Knitr
- Attribute Value Matrices
Class files
- Understanding packages and class files
- List of packages and class files
- Writing your own package
- Writing your own class
Advanced TeX/LaTeX
