diff --git a/lib/hypervisor/hv_xen.py b/lib/hypervisor/hv_xen.py
index 5a8e4a257f17507e88d204f3cfaa979824f7b5c7..75773abc6dfee4a1a4f8eeca1110767e6b58d19c 100644
--- a/lib/hypervisor/hv_xen.py
+++ b/lib/hypervisor/hv_xen.py
@@ -515,12 +515,16 @@ class XenHvmHypervisor(XenHypervisor):
     # device type checks
     nic_type = hvparams[constants.HV_NIC_TYPE]
     if nic_type not in constants.HT_HVM_VALID_NIC_TYPES:
-      raise errors.HypervisorError("Invalid NIC type %s specified for Xen HVM"
-                                   " hypervisor" % nic_type)
+      raise errors.HypervisorError("Invalid NIC type %s specified for the Xen"
+                                   " HVM hypervisor. Please choose one of: %s"
+                                   % (nic_type,
+                                      constants.HT_HVM_VALID_NIC_TYPES))
     disk_type = hvparams[constants.HV_DISK_TYPE]
     if disk_type not in constants.HT_HVM_VALID_DISK_TYPES:
-      raise errors.HypervisorError("Invalid disk type %s specified for Xen HVM"
-                                   " hypervisor" % disk_type)
+      raise errors.HypervisorError("Invalid disk type %s specified for the Xen"
+                                   " HVM hypervisor. Please choose one of: %s"
+                                   % (disk_type,
+                                      constants.HT_HVM_VALID_DISK_TYPES))
     # vnc_bind_address verification
     vnc_bind_address = hvparams[constants.HV_VNC_BIND_ADDRESS]
     if vnc_bind_address is not None: