after turned off my N90, and when I turned it on, it showed me the message "Phone start-up failed, contact the retailer" as the pictures attached.
I don't know what happen. Pls help !!!

http://www.allaboutsymbian.com/forum/attachment.php?attachmentid=3133&stc=1&d=1150940366

http://www.allaboutsymbian.com/forum/attachment.php?attachmentid=3134&stc=1&d=1150940366

http://www.allaboutsymbian.com/forum/attachment.php?attachmentid=3135&stc=1&d=1150940366

happened to me on my 6630
switch off the phone and remove the memory card then try to start the phone, if it works the mmc is corrupt if not then you need to format the phone itself by holding down the keys on start up, i cant remember which ones but im sure if you dont know a search will give you the answer.

Press and hold these three keys together

-Green dial key,
-Star key (*)
-Three key (3)

then press the power on/off to swtich on the N90 phone.

Do not let go the three keys until you see the "formatting" screen displayed

After a few minutes, the format will be complete. Your N90 will now be at its original factory settings.

Press and hold these three keys together

-Green dial key,
-Star key (*)
-Three key (3)

then press the power on/off to swtich on the N90 phone.

Do not let go the three keys until you see the "formatting" screen displayed

After a few minutes, the format will be complete. Your N90 will now be at its original factory settings.

I tried, but this way of formatting and even upgrading firmware cannot help to fix this error. I don't know what the error it is because the message is too general.

did you take the memory card out??

did you take the memory card out??
Yes, but it cannot help.