diff --git a/engine/orchestration/src/com/cloud/vm/VirtualMachineManagerImpl.java b/engine/orchestration/src/com/cloud/vm/VirtualMachineManagerImpl.java
index 2b244ef6ab9..5096ed4759e 100755
--- a/engine/orchestration/src/com/cloud/vm/VirtualMachineManagerImpl.java
+++ b/engine/orchestration/src/com/cloud/vm/VirtualMachineManagerImpl.java
@@ -2974,18 +2974,6 @@ public class VirtualMachineManagerImpl extends ManagerBase implements VirtualMac
         HypervisorGuru hvGuru = _hvGuruMgr.getGuru(vmProfile.getVirtualMachine().getHypervisorType());
         VirtualMachineTO vmTO = hvGuru.implement(vmProfile);
 
-        // don't delete default NIC on a user VM
-        if (nic.isDefaultNic() && vm.getType() == VirtualMachine.Type.User) {
-            s_logger.warn("Failed to remove nic from " + vm + " in " + network + ", nic is default.");
-            throw new CloudRuntimeException("Failed to remove nic from " + vm + " in " + network + ", nic is default.");
-        }
-
-        // if specified nic is associated with PF/LB/Static NAT
-        if (rulesMgr.listAssociatedRulesForGuestNic(nic).size() > 0) {
-            throw new CloudRuntimeException("Failed to remove nic from " + vm + " in " + network +
-                    ", nic has associated Port forwarding or Load balancer or Static NAT rules.");
-        }
-
         NicProfile nicProfile =
                 new NicProfile(nic, network, nic.getBroadcastUri(), nic.getIsolationUri(), _networkModel.getNetworkRate(network.getId(), vm.getId()),
                         _networkModel.isSecurityGroupSupportedInNetwork(network), _networkModel.getNetworkTag(vmProfile.getVirtualMachine().getHypervisorType(), network));
diff --git a/server/src/com/cloud/api/ApiAsyncJobDispatcher.java b/server/src/com/cloud/api/ApiAsyncJobDispatcher.java
index 71adf2ad344..0b7d681ad95 100644
--- a/server/src/com/cloud/api/ApiAsyncJobDispatcher.java
+++ b/server/src/com/cloud/api/ApiAsyncJobDispatcher.java
@@ -37,6 +37,7 @@ import org.apache.cloudstack.framework.jobs.AsyncJobDispatcher;
 import org.apache.cloudstack.framework.jobs.AsyncJobManager;
 import org.apache.cloudstack.jobs.JobInfo;
 
+import com.cloud.exception.InvalidParameterValueException;
 import com.cloud.user.Account;
 import com.cloud.user.User;
 import com.cloud.utils.component.AdapterBase;
@@ -77,7 +78,6 @@ public class ApiAsyncJobDispatcher extends AdapterBase implements AsyncJobDispat
             String acctIdStr = params.get("ctxAccountId");
             String contextDetails = params.get("ctxDetails");
 
-
             Long userId = null;
             Account accountObject = null;
 
@@ -109,6 +109,8 @@ public class ApiAsyncJobDispatcher extends AdapterBase implements AsyncJobDispat
 
                 // serialize this to the async job table
                 _asyncJobMgr.completeAsyncJob(job.getId(), JobInfo.Status.SUCCEEDED, 0, ApiSerializerHelper.toSerializedString(cmdObj.getResponseObject()));
+            } catch (InvalidParameterValueException ipve) {
+                throw new ServerApiException(ApiErrorCode.PARAM_ERROR, ipve.getMessage());
             } finally {
                 CallContext.unregister();
             }
diff --git a/server/src/com/cloud/vm/UserVmManagerImpl.java b/server/src/com/cloud/vm/UserVmManagerImpl.java
index abb5b7bb190..018c06291b4 100755
--- a/server/src/com/cloud/vm/UserVmManagerImpl.java
+++ b/server/src/com/cloud/vm/UserVmManagerImpl.java
@@ -37,7 +37,6 @@ import javax.naming.ConfigurationException;
 
 import org.apache.commons.codec.binary.Base64;
 import org.apache.log4j.Logger;
-
 import org.apache.cloudstack.acl.ControlledEntity.ACLType;
 import org.apache.cloudstack.acl.SecurityChecker.AccessType;
 import org.apache.cloudstack.affinity.AffinityGroupService;
@@ -1074,7 +1073,7 @@ public class UserVmManagerImpl extends ManagerBase implements UserVmManager, Vir
 
         UserVmVO vmInstance = _vmDao.findById(vmId);
         if (vmInstance == null) {
-            throw new InvalidParameterValueException("unable to find a virtual machine with id " + vmId);
+            throw new InvalidParameterValueException("Unable to find a virtual machine with id " + vmId);
         }
 
         // Check that Vm does not have VM Snapshots
@@ -1084,11 +1083,12 @@ public class UserVmManagerImpl extends ManagerBase implements UserVmManager, Vir
 
         NicVO nic = _nicDao.findById(nicId);
         if (nic == null) {
-            throw new InvalidParameterValueException("unable to find a nic with id " + nicId);
+            throw new InvalidParameterValueException("Unable to find a nic with id " + nicId);
         }
+
         NetworkVO network = _networkDao.findById(nic.getNetworkId());
         if (network == null) {
-            throw new InvalidParameterValueException("unable to find a network with id " + nic.getNetworkId());
+            throw new InvalidParameterValueException("Unable to find a network with id " + nic.getNetworkId());
         }
 
         // Perform permission check on VM
@@ -1097,19 +1097,28 @@ public class UserVmManagerImpl extends ManagerBase implements UserVmManager, Vir
         // Verify that zone is not Basic
         DataCenterVO dc = _dcDao.findById(vmInstance.getDataCenterId());
         if (dc.getNetworkType() == DataCenter.NetworkType.Basic) {
-            throw new CloudRuntimeException("Zone " + vmInstance.getDataCenterId() + ", has a NetworkType of Basic. Can't remove a NIC from a VM on a Basic Network");
+            throw new InvalidParameterValueException("Zone " + vmInstance.getDataCenterId() + ", has a NetworkType of Basic. Can't remove a NIC from a VM on a Basic Network");
         }
 
-        //check to see if nic is attached to VM
+        // check to see if nic is attached to VM
         if (nic.getInstanceId() != vmId) {
-            throw new InvalidParameterValueException(nic + " is not a nic on  " + vmInstance);
+            throw new InvalidParameterValueException(nic + " is not a nic on " + vmInstance);
         }
 
         // Perform account permission check on network
         _accountMgr.checkAccess(caller, AccessType.UseEntry, false, network);
 
-        boolean nicremoved = false;
+        // don't delete default NIC on a user VM
+        if (nic.isDefaultNic() && vmInstance.getType() == VirtualMachine.Type.User) {
+            throw new InvalidParameterValueException("Unable to remove nic from " + vmInstance + " in " + network + ", nic is default.");
+        }
 
+        // if specified nic is associated with PF/LB/Static NAT
+        if (_rulesMgr.listAssociatedRulesForGuestNic(nic).size() > 0) {
+            throw new InvalidParameterValueException("Unable to remove nic from " + vmInstance + " in " + network + ", nic has associated Port forwarding or Load balancer or Static NAT rules.");
+        }
+
+        boolean nicremoved = false;
         try {
             nicremoved = _itMgr.removeNicFromVm(vmInstance, nic);
         } catch (ResourceUnavailableException e) {
@@ -1125,7 +1134,6 @@ public class UserVmManagerImpl extends ManagerBase implements UserVmManager, Vir
 
         s_logger.debug("Successful removal of " + network + " from " + vmInstance);
         return _vmDao.findById(vmInstance.getId());
-
     }
 
     @Override