web site data will not delete from my Mac

Deleted Website Data reappearing?

Safari 10

Website Data comprises of Caches, Cookies, Local Storage and and Databases.

Cookies and Caches help Safari run faster by storing relevant information locally.

But you can remove all those website data without any problem, it may even help.

Next time you visit the site, related cookies will be restored.

Websites one visits may have links embedded in to other web sites.

Those sites will store cookies in the cookies folder.

Cookies may not have the same name as the original website.

The homepage I have set, adds about 70 cookies.

A website may use service from other service providers.

When a user signs into ASC, a cookie from Badgeville will appear.

Cookies from websites added to AutoFill will appear automatically.

Websites that are related to widgets like Weather channel will reappear.

Cookies from built in search engines like Bing, Yahoo and other favorites like Facebook will reappear.

One of these may add additional cookies.

Cookies can come from Plug-ins and extensions installed on our Mac. There are Flash cookies.

Cookies from some of the bookmarks/favorites sites will reappear.

macOS stores cookies in different folders like Cookies folder, Databases folder, Local Storage folder, etc

It is not easy to track down these cookies. There are”Evercookies” that are hard to delete.

How to remove website data user accessible storage locations?

1. Empty Caches

Safari > Preference > Advanced

Checkmark the box beside "Show Develop menu in menu bar".

Develop menu will appear in the Safari menu bar.

Click Develop and select "Empty Caches" from the dropdown.

2. Delete Cookies

Safari > Preferences > Privacy > Cookies and Website Data...:

Click the “Manage Website Data” button.

Remove all cookies except ones from Apple, your internet service provider and banks.

3. Delete Databases and Local Storage items

Quit Safari.

Hold the Option key on the keyboard down and click the “Go”menu in the Finder menu bar.

Choose “Library” from the dropdown.

Scroll down the list.

Click open the Safari folder.

Scroll down the list and click open the “Databases” folder and then IndexedDB folder.

If you find the items there right click and choose “Move to Trash”.

Scroll down the list and click open the “Local Storage” folder

Right click the items you want remove and right click it and choose “Move to Trash”.

As per this article : Safari for Mac: Manage cookies and website data using Safari

Websites often store cookies and other data on your Mac. This data may include information that you have provided, such as your name, email address, and preferences. This data helps websites identify you when you return so the site can provide services for you and show information that might be of interest to you.

By default, Safari accepts cookies and website data only from websites you visit. This helps prevent certain advertisers from storing data on your Mac. You can change options in Safari preferences so that Safari always accepts or always blocks cookies and other website data.

Important: Changing your cookie preferences or removing cookies and website data in Safari may change or remove them in other apps, including Dashboard.

Enter in the user library : macOS Sierra: Library folder

Find a folder safari > Local storage > you can see local storage is stored shown with the red arrow while browsing the website multiple times .

Then , in the same user library delete the entire contents of Caches , Cookies into the trash , restart the machine and empty the trash .

Local storage data gets empty for the time being ( you can see in the above screen shot ) , but when again you visit the website the data will automatically filled up for the second time , it means websites need cookies , to run smoothly .

Caches and cookies are temp files that will always be generated in the user library .

Permanent removal method of data base is not practically possible in normal browsing , if the user wants that website data should never to be saved in local storage can use private browsing mode : Safari for Mac: Use Private Browsing windows in Safari

As a test, disable iCloud syncing and test.

System Preferences > iCloud > Safari

Once testing done, reenable it and test.