From: Peter Weldon Date: 2010-09-14T00:48:09+09:00 Subject: [ruby-core:32363] [Ruby 1.9-Bug#3825] ENV.delete raise Exception on Windows Issue #3825 has been updated by Peter Weldon. Knowing the value of GetLastError() after SetEnvironmentVariable() fails may give a clue. Can you try get that? In VS, I would, add "$err,hr" to my watch window and put a break point at the fail: label in hash.c (setenv). ---------------------------------------- http://redmine.ruby-lang.org/issues/show/3825 ---------------------------------------- http://redmine.ruby-lang.org