ASP.NET - Ajax Model POpup Extender is not working?

i have  one page on that i have one button ,when press the button  Model popup extender  will open with the  following information.

in first row i have  one Fileupload control and  upload button,
in second row i have one datalist with delete button inside.
in third row i have one submit button.

flow:  after selecting files with fileupload control ,i press upload button,then all the files will come and sit in datalist.
after that if  press submit button then all the files go and save in root directory folder,and path to Db.

Problem:  after selecting the files when i press the  upload button the model popup control is going.

How can i solve this  problem by using update panel...

Please follow this one:

i didn't get you one here ,from   your words that 'please  follow this one"

For this you can explicitly show popup again using show() method.

Like this-

MPopUp.Show();

Write this where you want to show popup again.