* installing *source* package ‘MUGS’ ...
** this is package ‘MUGS’ version ‘0.1.0’
** using staged installation
** R
** byte-compile and prepare package for lazy loading
** help
*** installing help indices
*** copying figures
** building package indices
** installing vignettes
Warning in file(con, "w") :
  cannot open file '/srv/hornik/tmp/CRAN_pretest/MUGS.Rcheck/00LOCK-MUGS/00new/MUGS/doc/index.html': No such file or directory
Calls: <Anonymous> ... installer -> .writeVignetteHtmlIndex -> writeLines -> file
Error in file(con, "w") : cannot open the connection
ERROR: installing vignettes failed
* removing ‘/srv/hornik/tmp/CRAN_pretest/MUGS.Rcheck/MUGS’