Remote Desktop Connection Issues

Hi Experts,

I have a user logging into one of our servers via RDP so they can use a specific application whilst offsite. However they quite regularly get the below error.

Your computer can't connect to the remote computer because an error occurred on the remote computer that you want to connect to. Contact your network administrator for administrator

On the server there is an event logged as below:

Log Name:      Application
Source:        Microsoft-Windows-Winlogon
Date:          12/18/2013 1:53:17 PM
Event ID:      4005
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      remotedekstopserver.domain.local
Description:
The Windows logon process has unexpectedly terminated.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="Microsoft-Windows-Winlogon" Guid="{DBE9B383-7CF3-4331-91CC-A3CB16A3B538}" EventSourceName="Winlogon" />
    <EventID Qualifiers="49152">4005</EventID>
    <Version>0</Version>
    <Level>2</Level>
    <Task>0</Task>
    <Opcode>0</Opcode>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2013-12-18T02:53:17.000000000Z" />
    <EventRecordID>78518</EventRecordID>
    <Correlation />
    <Execution ProcessID="0" ThreadID="0" />
    <Channel>Application</Channel>
    <Computer>remotedekstopserver.domain.local</Computer>
    <Security />
  </System>
  <EventData>
    <Binary>1F000000</Binary>
  </EventData>
</Event>

I can't identify what is causing it, it seems to be site specific as we don't have issues anywhere else.

The server is 2008 R2 standard running Remote Desktop Services, SQL and some L.O.B apps.

Any help would be greatly appreciated!