Feature #3: Server SKU support for Enrolment

The Disco Client (which is launched by the Bootstrapper) supports
Windows Server SKUs. Removes dependancy on WLANAPI.DLL. Updates to
enrolment allows for successful addition to System Critial objects (eg.
DC/PDCs) into Disco without making any changes to AD objects.

Disco.BI/BI/DeviceBI/Enrol.cs

@@ -481,7 +481,7 @@ namespace Disco.BI.DeviceBI
                     response.DeviceDomainName = MachineInfo.Domain;
 
                     // Enforce Computer Name Convention
-                    if (RepoDevice.DeviceProfile.EnforceComputerNameConvention)
+                    if (!MachineInfo.IsCriticalSystemObject && RepoDevice.DeviceProfile.EnforceComputerNameConvention)
                     {
                         var calculatedComputerName = RepoDevice.ComputerNameRender(Database);
                         if (!Request.DeviceComputerName.Equals(calculatedComputerName, StringComparison.InvariantCultureIgnoreCase))
@@ -499,7 +499,7 @@ namespace Disco.BI.DeviceBI
                     }
 
                     // Enforce Organisation Unit
-                    if (response.OfflineDomainJoin == null && RepoDevice.DeviceProfile.EnforceOrganisationalUnit)
+                    if (!MachineInfo.IsCriticalSystemObject && response.OfflineDomainJoin == null && RepoDevice.DeviceProfile.EnforceOrganisationalUnit)
                     {
                         var parentDistinguishedName = MachineInfo.ParentDistinguishedName();
 
@@ -518,7 +518,7 @@ namespace Disco.BI.DeviceBI
                     }
 
                 }
-                if (MachineInfo != null)
+                if (MachineInfo != null && !MachineInfo.IsCriticalSystemObject)
                 {
                     EnrolmentLog.LogSessionProgress(sessionId, 75, "Updating Active Directory Computer Account Properties");
                     MachineInfo.UpdateNetbootGUID(Request.DeviceUUID, Request.DeviceLanMacAddress);

Disco.BI/BI/Extensions/DeviceActionExtensions.cs

@@ -93,7 +93,7 @@ namespace Disco.BI.Extensions
             if (d.ComputerName != null)
             {
                 var adAccount = d.ActiveDirectoryAccount();
-                if (adAccount != null)
+                if (adAccount != null && !adAccount.IsCriticalSystemObject)
                 {
                     adAccount.DisableAccount();
                 }
@@ -120,7 +120,7 @@ namespace Disco.BI.Extensions
             if (d.ComputerName != null)
             {
                 var adAccount = d.ActiveDirectoryAccount();
-                if (adAccount != null)
+                if (adAccount != null && !adAccount.IsCriticalSystemObject)
                 {
                     adAccount.EnableAccount();
                 }

Disco.Client/Interop/Network.cs

@@ -21,7 +21,15 @@ namespace Disco.Client.Interop
             if (NetworkAdapters.Count > 0)
             {
                 // Only Retrieve Wlan Adapters if at least one adapter was found by WMI
-                RetrieveWlanAdapters();
+                try
+                {
+                    RetrieveWlanAdapters();
+                }
+                catch (DllNotFoundException)
+                {
+                    // Ignore DllNotFoundException
+                    // This which indicates 'Wlanapi.dll' isn't present (eg. Windows Servers)
+                }
 
                 // Determine Primary Adapters