The error msg I got is: Flash Player Plugin on Linux 11.2.202.643 to 23.0.0.207 (click-to-play) has been blocked for your protection. But for Linux the latest version available is 11.2.202.644, which _is_ the version I'm using, Adobe doesn't create any higher versions for LINUX anymore, although they still DO update 11.2.202 for security fixes. Furthermore the page also complains about my version of Firefox: Looks like you’re using an older version of Firefox. but it is version 45.6.0esr, which IS the newest available in the esr range. RHEL/CentOS 6 do _not_ support the non-esr versions of Firefox but they DO deliver the latest ESR one: firefox-45.6.0-1.i686.rpm So your test should also allow the latest esr version of firefox. PS: I have to use the 686 version of the O/S and firefox as this cpu (AMD Athlon 2800+) doesn't support 64-bit mode (RHEL/CentOS 7 is only available in a x86_64 version).