Native WiFi function 'WlanSetProfileEapXmlUserData' returns an error when attempting to set credentials.

I am trying to use the Native WiFi API on Windows Vista to connect to
an access point via WPA2 using PEAPv0/EAP-MSCHAPv2. I can connect to the
access point via the API just fine when Windows automatically uses my
Windows account user credentials for the authentication. However, when I
try to specifically set my credentials using WlanSetProfileEapXmlUserData,
the function returns error 127. Also, in the debugger output window, the
following line appears after calling the function:

First-chance exception at 0x762242eb in Wireless Utility.exe:
Microsoft C++ exception: EapHost::EapException at memory location
0x020cf140..

I am using the following xml for my credentials in the function. Is
there something wrong with my xml? What else could be causing the error?

<?xml version="1.0" ?>
<EapHostUserCredentials
xmlns="http://www.microsoft.com/provisioning/EapHostUserCredentials"
xmlns:eapCommon="http://www.microsoft.com/provisioning/EapCommon"
xmlns:baseEap="http://www.microsoft.com/provisioning/BaseEapMethodUserCredentials">
<EapMethod>
<eapCommon:Type>25</eapCommon:Type>
<eapCommon:AuthorId>0</eapCommon:AuthorId>
</EapMethod>
<Credentials
xmlns:eapUser="http://www.microsoft.com/provisioning/EapUserPropertiesV1"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:baseEap="http://www.microsoft.com/provisioning/BaseEapUserPropertiesV1"
xmlns:MsPeap="http://www.microsoft.com/provisioning/MsPeapUserPropertiesV1"
xmlns:MsChapV2="http://www.microsoft.com/provisioning/MsChapV2UserPropertiesV1">
<baseEap:Eap>
<baseEap:Type>25</baseEap:Type>
<MsPeap:EapType>

<MsPeap:RoutingIdentity>bhaddock</MsPeap:RoutingIdentity>
<baseEap:Eap>
<baseEap:Type>26</baseEap:Type>
<MsChapV2:EapType>
<MsChapV2:Username>bhaddock</MsChapV2:Username>
<MsChapV2:Password>test</MsChapV2:Password>
<MsChapV2:LogonDomain>CP</MsChapV2:LogonDomain>
</MsChapV2:EapType>
</baseEap:Eap>
</MsPeap:EapType>
</baseEap:Eap>
</Credentials>
</EapHostUserCredentials>

Here is a copy of the xml for the WPA2 with PEAP profile I've created
using WlanSetProfile:

<?xml version="1.0"?>
<WLANProfile
xmlns="http://www.microsoft.com/networking/WLAN/profile/v1">
<name>MBR-3a8</name>
<SSIDConfig>
<SSID>
<name>MBR-3a8</name>
</SSID>
</SSIDConfig>
<connectionType>ESS</connectionType>
<MSM>
<security>
<authEncryption>
<authentication>WPA2</authentication>
<encryption>TKIP</encryption>
<useOneX>true</useOneX>
</authEncryption>
<OneX xmlns="http://www.microsoft.com/networking/OneX/v1">
<EAPConfig>
<EapHostConfig
xmlns="http://www.microsoft.com/provisioning/EapHostConfig">
<EapMethod>
<Type
xmlns="http://www.microsoft.com/provisioning/EapCommon">25</Type>
<AuthorId
xmlns="http://www.microsoft.com/provisioning/EapCommon">0</AuthorId>
</EapMethod>
<ConfigBlob/>
</EapHostConfig>
</EAPConfig>
</OneX>
</security>
</MSM>
</WLANProfile>

Thanks for your help. I need to be able to allow the user to change
their credentials using the utility I am writing, but I haven't been able to
figure out what is causing this issue.

Best Regards,

Brendan

(E-Mail Removed)