Windows security update is stopping all QlikView 11.20 servers - security patch for Ransomware affecting

As part of the latest Windows update ( around the May 2017 ) It appears that certain Windows KB files are updating the TLS version on the Windows server to the latest TLS version 1.2

As a result of this TLS update, QlikView 11.2.0 servers that are older than SR15 are stopping and generating errors related to SSL: Decrypt . (Transport Layer Security (TLS)  and mentioned below.

QlikView versions 11.2.0 older than SR15 do not support the newer version of TLS 1.2

The solution is to update to QlikView 11.2.0 SR16,  QlikView 12.10 SR6  or later which supports TLS 1.2. 

If you are considering to update the latest Microsoft patch due to the WannaCry ransonware (ransom), Qlik advise to plan moving to QlikView 11.20 SR 16, test this version then perform the Microsoft security patch.

For more information about QlikView and TLS 1.2 support please refer to the article: SSL & TLS Support in QlikView - How to configure QlikView and TLS

For example you may see errors such as the one below ( in the QlikView event logs ) :

Error    SSL: Decrypt Message Error: -2146893008
Error    SSL: Main loop error: -1


Further information regarding Security Patches from Microsoft: https://blogs.technet.microsoft.com/msrc/2017/05/12/customer-guidance-for-wannacrypt-attacks/