> For the complete documentation index, see [llms.txt](https://overleaf-pro.ayaka.space/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://overleaf-pro.ayaka.space/latex/latex-basics/05-errors.md). # Errors LaTeX error messages can sometimes be tricky to understand and fix. We've put together a list of common errors below, along with more information about what they mean and how to solve them. ## Alignment * [Misplaced alignment tab character &](/latex/latex-errors/23-misplaced-alignment-tab-character.md) * [Extra alignment tab has been changed to \cr.](/latex/latex-errors/07-extra-alignment-tab-has-been-changed-to-cr.md) ## Double subscript * [Double subscript](/latex/latex-errors/04-double-subscript.md) ## Missing Math mode characters * [Display math should end with $$](/latex/latex-errors/03-display-math-should-end-with.md) * [Missing $ inserted](/latex/latex-errors/25-missing-inserted.md) ## References * [There were undefined references](/latex/latex-errors/30-there-were-undefined-references.md) * [Reference XXX on page XXX undefined on input line XXX](/latex/latex-errors/30-there-were-undefined-references.md) ## Labeling * [There were multiply-defined labels.](/latex/latex-errors/29-there-were-multiply-defined-labels.md) * [Label XXX multiply defined.](/latex/latex-errors/29-there-were-multiply-defined-labels.md) ## Float specifiers * [\`h' float specifier changed to \`ht'.](/latex/latex-errors/01-h-float-specifier-changed-to-ht.md) * [No positions in optional float specifier.](/latex/latex-errors/28-no-positions-in-optional-float-specifier.md) ## Undefined control sequences * [Undefined control sequence.](/latex/latex-errors/31-undefined-control-sequence.md) ## File not found * [File XXX not found on input line XXX."](/latex/latex-errors/09-file-xxx-not-found-on-input-line-xxx.md) * [LaTeX Error: File XXX not found."](/latex/latex-errors/09-file-xxx-not-found-on-input-line-xxx.md) * [Package pdftex.def Error: File XXX not found."](/latex/latex-errors/09-file-xxx-not-found-on-input-line-xxx.md) ## Missing number/illegal units of measure * [Missing number, treated as zero](/latex/latex-errors/26-missing-number-treated-as-zero.md) * [Illegal unit of measure (pt inserted)](/latex/latex-errors/10-illegal-unit-of-measure-pt-inserted.md) ## Environment undefined (missing package) * [LaTeX Error: Environment tikzpicture undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment theorem undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment split undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment minipage\* undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment maplelatex undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment mapleinput undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment maplegroup undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment flalign undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment figure\* undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment comment undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment biblio\_lat undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment align\* undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment align undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment algorithm undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) * [LaTeX Error: Environment adjustbox undefined](/latex/latex-errors/14-latex-error-environment-xxx-undefined.md) ## Underfull and overfull boxes Although these warnings are *not* errors we list them here for convenience: * [Understanding underfull and overfull box warning](/latex/knowledge-base/138-understanding-underfull-and-overfull-box-warnings.md) ## Other * [LaTeX Error: Can be used only in preamble](/latex/latex-errors/13-latex-error-can-be-used-only-in-preamble.md) * [LaTeX Error: Missing \begindocument](/latex/latex-errors/16-latex-error-missing-begin-document.md) * [LaTeX Error: \verb ended by end of line](/latex/latex-errors/12-latex-error-verb-ended-by-end-of-line.md) * [No \author given](/latex/latex-errors/27-no-author-given.md) * [Misplaced \noalign](/latex/latex-errors/22-misplaced-noalign.md) * [LaTeX Error: Something's wrong--perhaps a missing \item](/latex/latex-errors/17-latex-error-something-s-wrong-perhaps-a-missing-item.md) * [There's no line here to end](/latex/latex-errors/18-latex-error-there-s-no-line-here-to-end.md) * [Unknown graphics extension: .XXX](/latex/latex-errors/21-latex-error-unknown-graphics-extension-.xxx.md) --- # Agent Instructions This documentation is published with GitBook. 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