COMException (0x80005000): Unknown error - UserPrincipal.set_GivenName(String value)

I have the following code which is called inside of an ASP.NET application:

public DomainUserInfo GetDomainUserInfoByName(string domain, string firstName, string lastName)
{
    string[] domainArray = domain.Split(',');
    foreach (string d in domainArray)
    {
        var principalContext = new PrincipalContext(ContextType.Domain, d);
        var userPrincipal = new UserPrincipal(principalContext) {GivenName = firstName, Surname = lastName};
        using (var searcher = new PrincipalSearcher(userPrincipal))
        {
            userPrincipal = (UserPrincipal) searcher.FindOne();
        }

        if (userPrincipal != null)
        {

            var domainUserInfo = new DomainUserInfo
            {
                FirstName = userPrincipal.GivenName,
                LastName = userPrincipal.Surname,
                Email = userPrincipal.EmailAddress,
                LanID = userPrincipal.SamAccountName,
                Extension = userPrincipal.VoiceTelephoneNumber,
                DomainName = d,
                NTAccountName = userPrincipal.Sid.Translate(typeof (NTAccount)).ToString()
            };

            return domainUserInfo;
        }
    }
    return null;
}

It works when deployed on some servers but not on others, where it throws the exception:

[COMException (0x80005000): Unknown error (0x80005000)]
   System.DirectoryServices.DirectoryEntry.Bind(Boolean throwIfFail) +386081
   System.DirectoryServices.DirectoryEntry.Bind() +36
   System.DirectoryServices.DirectoryEntry.get_AdsObject() +31
   System.DirectoryServices.PropertyValueCollection.PopulateList() +21
   System.DirectoryServices.PropertyValueCollection..ctor(DirectoryEntry entry, String propertyName) +49
   System.DirectoryServices.PropertyCollection.get_Item(String propertyName) +135
   System.DirectoryServices.AccountManagement.PrincipalContext.DoLDAPDirectoryInitNoContainer() +288
   System.DirectoryServices.AccountManagement.PrincipalContext.DoDomainInit() +37
   System.DirectoryServices.AccountManagement.PrincipalContext.Initialize() +118
   System.DirectoryServices.AccountManagement.PrincipalContext.ContextForType(Type t) +34
   System.DirectoryServices.AccountManagement.Principal.GetStoreCtxToUse() +37
   System.DirectoryServices.AccountManagement.UserPrincipal.set_GivenName(String value) +17
   Mfc.Inv.RM.Framework.ActiveDirectory.ActiveDirectoryManager.GetDomainUserInfoByName(String domain, String firstName, String lastName) +167

It looks like this is occurring on the line:

var userPrincipal = new UserPrincipal(principalContext) {GivenName = firstName, Surname = lastName};

when trying to set the GivenName property of the UserPrincipal object.

I'm totally stuck as to what could be causing this, especially since it works on some servers and not others. I already tried writing a console application that calls the same code it works on all of the servers, so I am guessing it has to be something to do with IIS.

here is what I am doing and if you were to hover over userFind or do a QuickWatch on it you will see the following information. also notice the IdentityType.SamAccountName that I am passing

var pc = new PrincipalContext(ContextType.Domain, domainName, null, null);
var userFind = UserPrincipal.FindByIdentity(pc, IdentityType.SamAccountName, username);