1) Type this into your Gmail search without the quotes. "label:inbox is:unread"
2) Select down arrow button and choose all.
3) In the top of your email will tell that 50 email is selected. you click on "Select all conversations that match this search"
4) Click on more and choose to select all as read.
5) Now you have done making all your inbox as read.
cPanel - Control Panel11
DNS - Nameserver10
Installing a Control Panel1
Mail Filters & SPAM11
Search Engine Optimization10
SiteWorx (Control Panel)60