[TYPO3-english] 4.2.10 Install Toll problems

[Victor Livakovsky]

Hi, List!

I have a problem, that appears from time to time at different TYPO3 
installations after upgarde from any 4.2.x to 4.2.10.
Install Tool becomes unaccessible, pop-up window appears every time, when I 
enter correct password and press 'Log In', and after that I can see same 
login form.
Password is correct and non-default, cookies enabled. If I change core to 
4.2.8 - this problem don't appear.

Maybe, I missed something? Or it is some core issue?

Thank you for any help.