ASP.NET Core Identity is not finding users via email after migrating from K13

[maciejdoboszadhd]

Brief bug description

After migrating users from Kentico 13 → Xperience by Kentico using the Xperience Migration Tool, users appear correctly in the CMS_User table, but ASP.NET Core Identity is unable to locate them using UserManager.FindByEmailAsync().
FindByEmailAsync() consistently returns null, even though the user record exists in the database with the correct email.

Output logs

protocol20251124_0827.txt

Repro steps

1. Migrate a Kentico 13 instance to Xperience by Kentico using the official migration tool.
2. Verify that users exist in the CMS_User table with correct values (including Email).
3. Configure ASP.NET Core Identity and the default Kentico ApplicationUserStore.
4. Attempt to authenticate a migrated user (note: migrated user was marked as external in Kentico 13).

Application attempts:
var user = await userManager.FindByEmailAsync(email);

FindByEmailAsync() returns null, and sign-in fails.

Inspecting the database shows the user is present and the email matches exactly.

Expected behavior

UserManager.FindByEmailAsync() should successfully locate users migrated from Kentico 13, using the email stored in the CMS_User.Email column.
Users should be recognized by the Identity system without requiring additional manual intervention or re-saving user records post-migration.
Email fields should be properly mapped and normalized by the Xperience-provided ApplicationUserStore.

Test environment

Platform/OS: Windows 11, .NET 8
Browser: Chrome 129
Xperience by Kentico version: 30.10.1
Migration Tool version: 3.16.0

Additional context

That's how my ASP.NET Core Identity has been configured

services.AddIdentity<ApplicationUser, NoOpApplicationRole>(options =>
{
         options.SignIn.RequireConfirmedAccount = false;
})
.AddUserStore<ApplicationUserStore<ApplicationUser>>()
.AddRoleStore<NoOpApplicationRoleStore>()
.AddUserManager<UserManager<ApplicationUser>>()
.AddSignInManager<SignInManager<ApplicationUser>>()
.AddDefaultTokenProviders();`

[radekzitta]

Hello Maciej,

Users with the privilege level Editor and higher are migrated as XbK admin users - CMS_User table.
Users with the privilege None are migrated as members (=live site users). These are migrated to the table CMS_Member. User password hashes are not preserved, so account owners must reset their passwords first.

See the documentation
Users
Members

From your log, I see that 10 users were migrated to the CMS_User table and 6 users were migrated to the CMS_Members table.

The UserManager/ApplicationUserStore works with Members. You don't mention in your description which accounts you specifically tried, but users migrated to the members table are valid for login only.

Do you use case-insensitive collation for your DB as described in the requirements? . By default, the UserManager normalizes the email value to uppercase, and this value is used in the database query as the value for the MemberEmail filter.