diff --git a/virtwho/virt/esx/esx.py b/virtwho/virt/esx/esx.py
index ab53899b..a113dbbc 100644
--- a/virtwho/virt/esx/esx.py
+++ b/virtwho/virt/esx/esx.py
@@ -339,9 +339,15 @@ def getVmUuid(self, vm):
                     elif item.value == "FALSE":
                         smbios_version_27 = False
 
-        if 'config.version' not in vm:
-            return s
-        version = int(vm['config.version'].split('-')[1])
+        self.logger.debug(f"ESX acpi.smbiosVersion2.7: {smbios_version_27}")
+
+        version = 0
+        if 'config.version' in vm:
+            version = int(vm['config.version'].split('-')[1])
+            self.logger.debug(f"ESX config.version: {version} ({vm['config.version']})")
+        else:
+            self.logger.debug("ESX config.version not present")
+
         if version >= 13 or smbios_version_27 is False:
             return s[6:8] + s[4:6] + s[2:4] + s[0:2] + "-" + s[11:13] + s[9:11] + "-" + s[16:18] + s[14:16] + s[18:]
         else: