diff --git a/src/main/java/net/rptools/maptool/client/AppUtil.java b/src/main/java/net/rptools/maptool/client/AppUtil.java
index e89e94caae..dc26950953 100644
--- a/src/main/java/net/rptools/maptool/client/AppUtil.java
+++ b/src/main/java/net/rptools/maptool/client/AppUtil.java
@@ -216,6 +216,11 @@ public static Path getInstallDirectory() {
       path = path.getParent().getParent().getParent();
     } else { // First try to find MapTool* directory in path
       while (path != null) {
+        if (path.getFileName() == null) {
+          // We have gone too far!
+          path = null;
+          break;
+        }
         if (path.getFileName().toString().matches("(?i).*maptool.*")) {
           break;
         }