Index: /trunk/src/VBox/Frontends/VirtualBox/src/globals/UIIconPool.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/globals/UIIconPool.cpp	(revision 73126)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/globals/UIIconPool.cpp	(revision 73127)
@@ -469,4 +469,7 @@
         if (m_guestOSTypeIconNames.contains(strOSTypeID))
             m_guestOSTypeIcons[strOSTypeID] = iconSet(m_guestOSTypeIconNames[strOSTypeID]);
+        /* Assign fallback icon if we do NOT have that 'guest OS type' registered: */
+        else if (!strOSTypeID.isNull())
+            m_guestOSTypeIcons[strOSTypeID] = iconSet(m_guestOSTypeIconNames["Other"]);
         /* Assign fallback icon if we do NOT have that 'guest OS type' known: */
         else