Restore factory settings

[AntonioR]

I left my phone to my friend because he never heard of xiaomi and wanted to check it out... worst decision ever, in just 20 minutes he did a real mess (note to self: in future treasure ur smartphone like gollum would the ring), he downloaded dozens of apps and filled up the memory.... problem is that after I unistalled all the memory won't be back to how it was and is now roughly 500 mb higher (had 3.8 gb free now I have 3.23 gb), I tried using the security tool to check if there were any residues, but won't clean it... also free ram has decreased and now I have around 230 mb of free ram whilst I had at least 300 mb earlier.

This happened yesterday at dinner, now I tried to sort this out for the whole afternoon without success.... I fear this may be cause by some sort of bloatware or (worst case scenario) virus.


How can I restore factory settings to get a fresh system?
ATM I am using EU rom (the seller preinstalled it before shipping) will I get it too If I use recovery or will it go back to CN firmware?

please help me thanks

 

[AntonioR]

following this guide, I'm hoping to not brick my phone....

http://en.miui.com/forum.php?mod=viewthread&tid=11242

 

[AntonioR]

ok apparently flashing it like that won't delete datas... so I selected reboot in recovery mode... it appeared MIUI recovery 2.0.1, i firstly chose english then there were 2 options: "WIPE AND RESET" and "UPDATE from zip", under "Wipe and reset" there are also 3 choices:"wipe cache", "wipe user data" and "wipe all data", wich one should i choose? I do not want to end up bricking my phone or deleting the IMEI.... please someone help me

 

[AntonioR]

ok i'm feeling adventurous so i went with wipe all data...wish me good luck!

 

[AntonioR]

ok successful restore