Error(s) in re-building vignettes:
--- re-building 'intro_naivebayes.Rnw' using knitr
Warning in system(paste(shQuote(texi2dvi), if (quiet) "--quiet" else "",  :
  running command '"C:\PROGRA~1\MiKTeX\miktex\bin\x64\texify.exe" --quiet --pdf "intro_naivebayes.tex" --max-iterations=20 -I "C:/r_packages/rinst/share/texmf/tex/latex" -I "C:/r_packages/rinst/share/texmf/bibtex/bst"' had status 1
Error: processing vignette 'intro_naivebayes.Rnw' failed with diagnostics:
running 'texi2dvi' on 'intro_naivebayes.tex' failed

LaTeX errors:
ignettes/intro_naivebayes.tex:119: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:129: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:140: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:385: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:391: Package xcolor Error: Undefined color `messa
gecolor'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:501: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:536: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:623: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:650: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.
ignettes/intro_naivebayes.tex:717: Package xcolor Error: Undefined color `fgcol
or'.

See the xcolor package documentation for explanation.
Type  H <return>  for immediate help.

--- failed re-building 'intro_naivebayes.Rnw'

SUMMARY: processing the following file failed:
  'intro_naivebayes.Rnw'

Error: Vignette re-building failed.
Execution halted