diff --git a/core/TempPath.php b/core/TempPath.php
index 4f3a94c85..0bc6645e5 100644
--- a/core/TempPath.php
+++ b/core/TempPath.php
@@ -12,7 +12,7 @@ function getTempFolder($base = null) {
 	$parent = getTempParentFolder($base);
 
 	// The actual temp folder is a subfolder of getTempParentFolder(), named by username and suffixed with currently used php-version
-	$phpversion = '-php' . preg_replace('/[^\w-\.+]+/', '-', PHP_VERSION);
+	$phpversion = '-php' . preg_replace('/[^\w\-\.+]+/', '-', PHP_VERSION);
 	$subfolder = $parent . DIRECTORY_SEPARATOR . getTempFolderUsername() . $phpversion;
 
 	if(!@file_exists($subfolder)) {
diff --git a/tests/core/CoreTest.php b/tests/core/CoreTest.php
index 5b4cc7510..06c716255 100644
--- a/tests/core/CoreTest.php
+++ b/tests/core/CoreTest.php
@@ -17,7 +17,7 @@ class CoreTest extends SapphireTest {
 
 	public function testGetTempPathInProject() {
 		$user = getTempFolderUsername();
-		$phpversion = '-php' . preg_replace('/[^\w-\.+]+/', '-', PHP_VERSION);
+		$phpversion = '-php' . preg_replace('/[^\w\-\.+]+/', '-', PHP_VERSION);
 		if(file_exists($this->tempPath)) {
 			$this->assertEquals(getTempFolder(BASE_PATH), $this->tempPath . DIRECTORY_SEPARATOR . $user . $phpversion);
 		} else {
@@ -43,9 +43,9 @@ class CoreTest extends SapphireTest {
 	public function tearDown() {
 		parent::tearDown();
 		$user = getTempFolderUsername();
-		$phpversion = '-php' . preg_replace('/[^\w-\.+]+/', '-', PHP_VERSION);
+		$phpversion = '-php' . preg_replace('/[^\w\-\.+]+/', '-', PHP_VERSION);
 		$base = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'silverstripe-cache' . $phpversion;
-		
+
 		foreach(array(
 			'C--inetpub-wwwroot-silverstripe-test-project',
 			'-Users-joebloggs-Sites-silverstripe-test-project',