Their "optimizer" usually causes more problems than it fixes. Many posters on these forums report problems on their computers after having used such.
And if you're referring to the problem with the WannaCry Ransomware, it's not necessary to block those ports as long as you have the Windows Updates installed. In fact, the SMB vulnerability was patched a couple of months ago by Microsoft, assuming you updated then. Blocking those particular ports on internal firewalls, which are used for file sharing, could cause problems if you share files and printers.
But if you're not sharing files on a network, the go ahead. Just realize it could cause sharing problems in the future.
Hope this helps.
Grif
Iobit has sent out a message telling Windows 10 users to manually block ports 445 tcp and 445 udp. Will installing today's Microsoft Security Updates take care of this by themselves?

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