Outlook 2007 Fault (Exception code: 0xc0000005)

I am starting Outlook 2007 in a .NET Windows Service on a Win7 (64 bit) Dell Optiplex760:

    app = new Microsoft.Office.Interop.Outlook.Application();
    ns = app.GetNamespace("MAPI");
    ns.Logon("faxagentdev", Missing.Value, false, true);

I get consistent Outlook faults Starting the service on one system and occasional faults on another system.  The events log:

Faulting application name: OUTLOOK.EXE, version: 12.0.6557.5001, time stamp: 0x4db1d555
Faulting module name: OUTLOOK.EXE, version: 12.0.6557.5001, time stamp: 0x4db1d555
Exception code: 0xc0000005
Fault offset: 0x000287ba
Faulting process id: 0x11ac
Faulting application start time: 0x01cc52e2e84b4be8
Faulting application path: C:\Program Files (x86)\Microsoft Office\Office12\OUTLOOK.EXE
Faulting module path: C:\Program Files (x86)\Microsoft Office\Office12\OUTLOOK.EXE
Report Id: 278ea168-bed6-11e0-a5fa-002564abef10


Then:
Fault bucket , type 0
Event Name: APPCRASH
Response: Not available
Cab Id: 0

Problem signature:
P1: OUTLOOK.EXE
P2: 12.0.6557.5001
P3: 4db1d555
P4: OUTLOOK.EXE
P5: 12.0.6557.5001
P6: 4db1d555
P7: c0000005
P8: 000287ba
P9:
P10:

Attached files:

These files may be available here:
C:\ProgramData\Microsoft\Windows\WER\ReportQueue\AppCrash_OUTLOOK.EXE_98081eb715953812441ce70fbec9234bb60063_1338fa45

Analysis symbol:
Rechecking for solution: 0
Report Id: 278ea168-bed6-11e0-a5fa-002564abef10
Report Status: 4

I've tried;
Rebuilding the faxagentdev mail profile.
Repairing Microsoft Office in Control Panel.
This is a new email account so the size of the Exchange mail store is not large.

Can anyone help?