Windows 8 lags at login

hi;
so when i login to windows it lags for about a minute and then starts working normally;
i don't know when exactly this happened, i mean after installing what app;
but the lag time is increasing day by day; !
help; ?

Win+X->Task Manager and click on Startup tab to find out how many items are set to run at startup. You need to decide which item is not needed and disable it by right click on the item, then select disable.

Maybe this is affecting your system:
http://www.eightforums.com/performance-maintenance/21875-delayeddesktopswitchtimeout-slow-login.html