diff --git a/appveyor.yml b/appveyor.yml
index ad5fa19..6de5d05 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -79,7 +79,7 @@ before_build:
             $env:Darch = "x86";
           }
         elseif($env:arch -eq "x86_mscoff"){
-            $env:compilersetupargs = "amd64";
+            $env:compilersetupargs = "x86";
             $env:Darch = "x86_mscoff";
         }
         elseif($env:arch -eq "x64"){
diff --git a/source/vibe/core/file.d b/source/vibe/core/file.d
index 9058d04..6b0cc99 100644
--- a/source/vibe/core/file.d
+++ b/source/vibe/core/file.d
@@ -144,9 +144,9 @@ FileStream createTempFile(string suffix = null)
 		import std.conv : to;
 		string tmpname;
 		() @trusted {
-			char[L_tmpnam] tmp;
-			tmpnam(tmp.ptr);
-			tmpname = to!string(tmp.ptr);
+			auto fn = tmpnam(null);
+			enforce(fn !is null, "Failed to generate temporary name.");
+			tmpname = to!string(fn);
 		} ();
 		if (tmpname.startsWith("\\")) tmpname = tmpname[1 .. $];
 		tmpname ~= suffix;