Most PCs affected by WannaCry running Windows 7

May 22nd 2017 

It has been reported that he majority of PCs infected by the WannaCry ransomware worm in last week's cyberattack were running Windows 7. Two security software firms have said that most used the older version of the Windows operating system, with Kaspersky Lab reporting 97% of infections affecting Windows 7 machines and BitSight putting the figure at 66%. So far, the ransomware is known to have affected more than 200,000 computers in over 150 countries, including a number of NHS trusts in the UK. Kaspersky has said that infections of Windows XP machines were "insignificant". The incident has highlighted the need to ensure operating systems – and all other software and apps – are updated as soon as users are prompted.

Advice for Windows users PLUS Microsoft patches to protect against 'WannaCry' ransomware 

Home & Small Business Users

Home users and small businesses can take the following steps to protect themselves:

– Run Windows Update

– Make sure your internet security (anti-virus, anti-spyware) software is up to date and switched on and run a scan. If you do not have internet security software installed, download one immediately. There are many reputable vendors and you can find reviews online. Most are relatively inexpensive and many cover multiple devices, including your phone and tablet.

– Ensure your data is backed up. If your system is affected by ransomware, it may well be that you are unable to access any data. We recommend online backup to one of the many cloud-based (online) services available … again you can find reviews online.

– Depending on the strain of ransomware your computer has been infected with and your level of technical ability, it may be possible for you to remove the infection yourself, but we emphasise that it is a complex process. US computer magazine PC World offers advice here:

Enterprise Administrators

It is recommended that the following steps be performed as a matter of urgency in order to contain the propagation of this this strain of ransomware:

– Deploy patch MS17-010:

– A new patch has been made available for legacy platforms, and is available here:




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