[Rd] update.packages fails with directory not found

[Mike Prager]

Windows XP.  I have just updated to R 2.11.0 and then run
update.packages. In the series of updates, a few will succeed, then I
get a failure like


package 'mvtnorm' successfully unpacked and MD5 sums checked
package 'party' successfully unpacked and MD5 sums checked
package 'PBSmodelling' successfully unpacked and MD5 sums checked
Error in normalizePath(path) : 
  path[1]="c:\Program Files\R\Library/PBSmodelling": The system cannot
find the file specified


Indeed, the path is missing, though it was there when I issued the
update.packages command.

???

--
Mike Prager, NC, USA