Not redirect to www only in homepage

[shahriar]

Hello , 

im using multistore , for Shop A i add only www.ShopA.com link 

 

i want  ShopA.com redirect to www.ShopA.com

 

PROBLEM IS :

 

if type in browser ShopA.com it will go to http://ShopA.com 

BUT

as soon as i click on product or log in page or etc. it will redirect to www.ShopA.com/Product-1

 

and when i am in www.ShopA/Product-1 page and click on home page it will show www.ShopA.com !

 

and when i just simply copy link ShopA.com/Product-1 and put in browser and enter i will get error that page not found in prestashop !

 

how can i solve this problem , that type ShopA.com it will redirect to www.ShopA.com for home page ?

 

 

[shahriar]

Please some one tell me how can i setting correct .htaccess for multi store that only redirect to www

 

 

the main address in browser

when im typing this link in my browser 

http://mysite.com/catrgory-name/Products-A.html

 

it will show me below error 

 

[Debug] This page has moved

Please use the following URL instead: http://www.mysite.com/catrgory-name/Products-A.html

 

Prestashop can not handle to regenerate .htaccess file correctly . it should be add some thing to .htaccess to work well