I will answer the "how to protect" part a little concisely

0. Act quickly

The malware is still spreading. If your system is unprotected, its remaining life is counted in hours

1. Make sure to perform required system updates

Microsoft has already released patches for all versions of Windows under maintenance. Perhaps Windows ME has not been patched, otherwise go to #4

2. Backup

You can defend your infrastructure by any ransomware, or at least limit its damage, by enforcing a valid backup policy. Backing up to a vulnerable machine is meaningless in this situation. Synchronizing to cloud can be dangerous

3. Firewall yourself from the outside

Both if you are a home user or an large enterprise, you shall always apply the firewall rule of thumb: disable everything except services you are actually running.

Running a web application? Open only ports 80/443. Running Torrent at home? Use upnp or choose your ports to open on your modem.

Do not use DMZ. If you really need SMB you have to think about it carefully. Discussing on ServerFault may be good.

#4. Air gap or strong-firewall old machines If you own a legacy system that is really business critical and can't be upgraded in short time, consider air-gapping it. Virtualizing an old Windows version is useless because the malware can spread on your network of outdated machines. If you fail to firewall and/or to disable SMB completely, the last option is to remove the network cable until you find a better solution

I will answer the "how to protect" part a little concisely

0. Act quickly

The malware is still spreading. If your system is unprotected, its remaining life is counted in hours

1. Make sure to perform required system updates

Microsoft has already released patches for all versions of Windows under maintenance. Perhaps Windows ME has not been patched, otherwise go to #4

2. Backup

You can defend your infrastructure by any ransomware, or at least limit its damage, by enforcing a valid backup policy. Backing up to a vulnerable machine is meaningless in this situation. Synchronizing to cloud can be dangerous

3. Firewall yourself from the outside

Both if you are a home user or an large enterprise, you shall always apply the firewall rule of thumb: disable everything except services you are actually running.

Running a web application? Open only ports 80/443. Running Torrent at home? Use upnp or choose your ports to open on your modem.

Do not use DMZ. If you really need SMB you have to think about it carefully. Discussing on ServerFault may be good.

4. Air gap or strong-firewall old machines

If you own a legacy system that is really business critical and can't be upgraded in short time, consider air-gapping it. Virtualizing an old Windows version is useless because the malware can spread on your network of outdated machines. If you fail to firewall and/or to disable SMB completely, the last option is to remove the network cable until you find a better solution