if login as Built-in Guest in windows 10 - explorer.exe permanent crashes and restart (desktop blinking). i found that error was in "virtual TokenBrokerMonitor::~TokenBrokerMonitor()" destructor - referenced some 0 pointer.
just before this was next string in debug output:
shell\roaming\settingsynccore\settingmonitor\tokenbrokermonitor.cpp(75)\SettingSyncCore.dll!00007FF9219C3000: (caller: 00007FF92FC8C524) ReturnHr[PreRelease](1) tid(f5c) D0000022
also now Guest account not listed under User Accounts\Manage Accounts . i research this too and found next:
in usercpl.dll was next code
if (m_bNotShowGuest) _RemoveGuestTile();
NTSTATUS CUserManager::Initialize(ILocalMachine*, ILogonEnumUsers*, int, int)
m_bNotShowGuest = true; // this statement is unconditional - always execute
as result _RemoveGuestTile(); always called. if remove m_bNotShowGuest = true; statement - Guest Tile begin shown.
so look like somebody special disable activation of Guest account, instead of fix bug in TokenBrokerMonitor::~TokenBrokerMonitor(). creative solution :)