Click 
→ Settings.
click → Settings
In the lower half of the Settings page, click Show advanced settings.
Click → Downloads.
Click → Extensions.
Click → Sync.
Click → Advanced → Clear history.
In the Passwords and forms section
Go to the Web content section.
Select the Internet security group.
In the Privacy section, click Content settings.
In the section with the name of the element you need, click Manage exceptions.
In the Privacy section, disable the Enable protection from malicious websites and software option.
In the Languages section, click Language and input settings.
To enable syncing:
Click the Disable button.
Turn on options that allow you to sync only the data you need.
In the Syncing section, click Show settings.
Click the delete link under the options.
At this point the browser offers to install the Yandex.Disk app, a service that lets you store files on Yandex servers for free. If you have already installed this app, the browser suggests you turn it on so that you can store browser files on Yandex.Disk.
In the Delete information? window, click Yes, delete to confirm that you want to delete all account data from the synchronization server.
Click Close.
Click the Enable syncing button.
Click Done.
Click OK.
Click Clear browsing data.
Restart the browser to apply the changes.
To disable malware protection
For more information, see the section
In the right part of SmartBox, click any Protect toolbar icon.
Click the More info link in the section where connection status displays in the window that appears.
Click the name of the desired file.
