Using RasGetEntryProperties in .NET CF

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C#

.NETCF

PInvoke

It seems that I can't get this right... I'm using the following signature:

[DllImport("coredll.dll")]
        private extern static uint RasGetEntryProperties(string lpszPhoneBook, string szEntry, ref RASENTRY lpbEntry,
            ref int lpdwEntrySize, byte lpb, ref int lpdwSize);

Calling it with the following parameters:

RasGetEntryProperties(null, name, ref RasEntry, ref dwSize, 0, 128);

However, whenever this is called, an error pops up on my device telling me there has been a native exception, without much detail.
I've declared the RASENTRY struct as follows:

private struct RASENTRY
        {
            public int dwSize;
            public int dwfOptions;
            public int dwCountryID;
            public int dwCountryCode;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxAreaCode + 1)]
            public string szAreaCode;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxPhoneNumber + 1)]
            public string szLocalPhoneNumber;
            public int dwAlternatesOffset;
            public RASIPADDR ipaddr;
            public RASIPADDR ipaddrDns;
            public RASIPADDR ipaddrDnsAlt;
            public RASIPADDR ipaddrWins;
            public RASIPADDR ipaddrWinsAlt;
            public int dwFrameSize;
            public int dwfNetProtocols;
            public int dwFramingProtocol;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH + 1)]
            public string szScript;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH + 1)]
            public string szAutoDialDll;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH + 1)]
            public string szAutoDialFunc;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxDeviceType + 1)]
            public string szDeviceType;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxDeviceName + 1)]
            public string szDeviceName;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxPadType + 1)]
            public string szX25PadType;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxX25Address + 1)]
            public string szX25Address;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxFacilities + 1)]
            public string szX25Facilities;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = RAS_MaxUserData + 1)]
            public string szX25UserData;
            public int dwChannels;
            public int dwReserved1;
            public int dwReserved2;
            public int dwCustomAuthKey;
        }

Any help would be appreciated, thanks!

-Brandon