Solution 1: Check to see if your internet connection is working If the time and date is not accurate, the appstore will refuse to connect.
Note: Before proceeding, make sure that you have accurate date and time on your machine. However, if none of these remedies manage to resolve this problem for you, fear not as the following are the most effective solutions that you can use to try and get rid of the “Cannot connect to the App Store” error message and re-establish a healthy connection to the Mac App Store: In most cases, simply closing and then re-launching the Mac App Store or logging out of the Mac App Store by clicking on Store > Logout and then logging back in to it fixes the problem. The cause behind this issue can be anything from a shaky internet connection to a problem with certificates in the Ke圜hain app. This is a problem in which the affected user’s Mac simply can’t connect to the Mac App Store. One of the most well-known problems with the Mac App Store is where it displays an error message stating “Cannot connect to the App Store” every time an affected user tries to launch it. However, the Mac App Store is not, like all other App Stores, without its fair share of kinks.
The Mac App Store is a wonderful place where you can download all kinds of applications and programs designed specifically for your Mac.