diff -r 56a5f80556f5 -r b6b0c42739e9 mercurial/util.py
--- a/mercurial/util.py	Mon Oct 05 22:57:15 2009 +0200
+++ b/mercurial/util.py	Tue Oct 06 16:08:38 2009 -0500
@@ -427,7 +427,14 @@
 
         temp = tempname(dst)
         os.rename(dst, temp)
-        os.unlink(temp)
+        try:
+            os.unlink(temp)
+        except:
+            # Some rude AV-scanners on Windows may cause the unlink to
+            # fail. Not aborting here just leaks the temp file, whereas
+            # aborting at this point may leave serious inconsistencies.
+            # Ideally, we would notify the user here.
+            pass
         os.rename(src, dst)
 
 def unlink(f):