Revert ac4ea65; only correct drive letter case.

Fixes #856, #815

2 files changed, 6 insertions, 2 deletions

diff --git a/docs/changes.rst b/docs/changes.rst
index 4ff0719..028154a 100644
--- a/docs/changes.rst
+++ b/docs/changes.rst
@@ -4,6 +4,8 @@ Release History
 14.1.0 (unreleased)
 -------------------
 
+* Revert ac4ea65; only correct drive letter case.
+  Fixes :issue:`856`, :issue:`815`
 
 14.0.3 (2016-01-28)
 -------------------
diff --git a/virtualenv.py b/virtualenv.py
index c8148f5..8fb53f6 100755
--- a/virtualenv.py
+++ b/virtualenv.py
@@ -975,10 +975,12 @@ def change_prefix(filename, dst_prefix):
         prefixes.append(sys.base_prefix)
     prefixes = list(map(os.path.expanduser, prefixes))
     prefixes = list(map(os.path.abspath, prefixes))
-    prefixes = list(map(os.path.normcase, prefixes))
     # Check longer prefixes first so we don't split in the middle of a filename
     prefixes = sorted(prefixes, key=len, reverse=True)
-    filename = os.path.normcase(os.path.abspath(filename))
+    filename = os.path.abspath(filename)
+    # On Windows, make sure drive letter is uppercase
+    if is_win and filename[0] in 'abcdefghijklmnopqrstuvwxyz':
+        filename = filename[0].upper() + filename[1:]
     for src_prefix in prefixes:
         if filename.startswith(src_prefix):
             _, relpath = filename.split(src_prefix, 1)