Windows 10: Fetching the user's email address

I found out that using the stored email used to sign in with Windows, Microsoft Live, Skype is the best way to determine (in all probability) the active email address of the user.


Windows stores used email accounts used as "Live ID" in the "UserExtendedProperties" key in

​

HKEY_CURRENT_USER\Software\Microsoft\IdentityCRL

The assumption is that this email was selected by the user as the Windows user name to log in to the PC and/or to other Windows services.

Therefore you can get the email accounts using the following code:

​

//
void GetDefaultEmailAddress()
{
HKEY key;
TCHAR achKey[MAX_KEY_LENGTH]; // buffer for subkey name
DWORD cbName; // size of name string
TCHAR achClass[MAX_PATH] = TEXT(""); // buffer for class name
DWORD cchClassName = MAX_PATH; // size of class string
DWORD cSubKeys = 0; // number of subkeys
DWORD cbMaxSubKey; // longest subkey size
DWORD cchMaxClass; // longest class string
DWORD cValues; // number of values for key
DWORD cchMaxValue; // longest value name
DWORD cbMaxValueData; // longest value data
DWORD cbSecurityDescriptor; // size of security descriptor
FILETIME ftLastWriteTime; // last write time

DWORD i, retCode;

TCHAR achValue[MAX_VALUE_NAME];
DWORD cchValue = MAX_VALUE_NAME;

if (RegOpenKeyEx(HKEY_CURRENT_USER, L"Software\\Microsoft\\IdentityCRL\\UserExtendedProperties", NULL, KEY_READ, &key) == ERROR_SUCCESS)
{
// Get the class name and the value count.
retCode = RegQueryInfoKey(
key, // key handle
achClass, // buffer for class name
&cchClassName, // size of class string
NULL, // reserved
&cSubKeys, // number of subkeys
&cbMaxSubKey, // longest subkey size
&cchMaxClass, // longest class string
&cValues, // number of values for this key
&cchMaxValue, // longest value name
&cbMaxValueData, // longest value data
&cbSecurityDescriptor, // security descriptor
&ftLastWriteTime); // last write time

// Enumerate the email accounts subkeys, until RegEnumKeyEx fails.

if (cSubKeys)
{
wprintf(TEXT("\nNumber of email accounts used: %d\n"), cSubKeys);

for (i = 0; i < cSubKeys; i++)
{
cbName = MAX_KEY_LENGTH;
retCode = RegEnumKeyEx(key, i,
achKey,
&cbName,
NULL,
NULL,
NULL,
&ftLastWriteTime);
if (retCode == ERROR_SUCCESS)
{
wprintf(TEXT("(%d) %s\n"), i + 1, achKey);
}
}
}
}
}

//

:)

 

different user accounts, only one email address?


Hi Geoff, welcome to the Ten Forums.

In Windows 10 it is not possible to use the same MS account for more than one user account on the same computer. If User-A signs in with an MS account User-A@AnyEmail.com, that MS account (email address) cannot be used to sign in any other user than User-A. User-B needs to use either a different MS account or a local account. However, you can use the same MS account on multiple computers.

There's no way to work around this restriction.

In your case I would simply install Windows 10 on both computers with a local admin account, then create an additional standard user account as an MS account on both computers using the same email address. If any of the two computers requires the gaming account, too, as you explained I would make this account a local account.

Tutorials:

• Clean install: Windows 10 - Clean Install - Windows 10 Forums (Step 23 shows how to make your initial admin account a local account)
• Create additional users: User Account - Add in Windows 10 - Windows 10 Forums (Option Four explains how to create the additional user as an MS account, Option Three how to create the gaming account as a local account)

 

Win10 Mail - where's the address book?


That’s now the People app.
If you know the contact's name or email address & they’re listed in the People app, you can start typing the first few letters of their name or email address and Mail for Windows 10 will suggest matching contacts.

 

Mail App: Removing drop down email address suggestions


I'm not a big fan of the MS Mail program and don't really use it for serious stuff but somehow or other if I create a new email then as I start to enter the recipients address a whole load of suggestions will appear. I don't have any contacts in the People app so I'm not sure where these come from.

The question is how can I clear this list so that I no longer get the suggestions?

Thanks