[BioC] Rgraphviz: .onLoad error

[Michael Friendly]

[Sysinfo: Win XP, R 2.8.1, graphviz 2.20]

I just tried to install and load Rgraphviz following the instructions at
http://www.bioconductor.org/packages/release/bioc/html/Rgraphviz.html
giving the error in the transcript below when I try to load the package.

I know from previous threads on R-help, e.g.,
http://finzi.psych.upenn.edu/R/Rhelp08/archive/137494.html
that versions of Rgraphviz and graphviz have to be in sync, graphviz 
(e.g., dot)
have to be on the path, etc. and I think I've satisfied these, but I get 
the same
error (.onLoad failed ...). 

Checking the .dll referred to in the message,
    unable to load shared library 
'C:/R/R-2.8.1/library/Rgraphviz/libs/Rgraphviz.dll':
shows that it is actually there.

What is wrong & how can I correct it?
-Michael


Graphviz version:
[HEALTH] C:\>dot -V
dot - Graphviz version 2.20.2 (Wed Jul  9 19:59:08 GMT 2008)


 > source("http://bioconductor.org/biocLite.R")
 >     biocLite("Rgraphviz")
Running biocinstall version 2.3.13 with R version 2.8.1
Your version of R requires version 2.3 of Bioconductor.
trying URL 
'http://bioconductor.org/packages/2.3/bioc/bin/windows/contrib/2.8/Rgraphviz_1.20.4.zip'
Content type 'application/zip' length 1008719 bytes (985 Kb)
opened URL
downloaded 985 Kb

package 'Rgraphviz' successfully unpacked and MD5 sums checked

The downloaded packages are in
        C:\Documents and Settings\default\Local 
Settings\Temp\Rtmp5a3NNx\downloaded_packages
updating HTML package descriptions
 > library(Rgraphviz)
Loading required package: graph
Error in inDL(x, as.logical(local), as.logical(now), ...) :
  unable to load shared library 
'C:/R/R-2.8.1/library/Rgraphviz/libs/Rgraphviz.dll':
  LoadLibrary failure:  The specified module could not be found.


Error : .onLoad failed in 'loadNamespace' for 'Rgraphviz'
Error: package/namespace load failed for 'Rgraphviz'
 > sessionInfo()
R version 2.8.1 (2008-12-22)
i386-pc-mingw32

locale:
LC_COLLATE=English_United States.1252;LC_CTYPE=English_United 
States.1252;LC_MONETARY=English_United 
States.1252;LC_NUMERIC=C;LC_TIME=English_United States.1252

attached base packages:
[1] grid      stats     graphics  grDevices utils     datasets  
methods   base    

other attached packages:
[1] graph_1.20.0    sem_0.9-16      rgl_0.84        psych_1.0-67    
lattice_0.17-22
[6] heplots_0.8-7   car_1.2-14    

loaded via a namespace (and not attached):
[1] cluster_1.11.13 tools_2.8.1   

-- 
Michael Friendly     Email: friendly AT yorku DOT ca 
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
4700 Keele Street    http://www.math.yorku.ca/SCS/friendly.html
Toronto, ONT  M3J 1P3 CANADA