Okay finally worked by a clean uninstallation and reinstallation as said in the link below (thank you all and also Mint Linden). I dunno why this plugen failed to install and I had to reinstall from another created user on the PC.
Dunno, but still cannot install the viewer, this says the plugin dll won't write on the PC... Even with the AV disabled. I've sent a ticket, maybe it's just me but anyway.
Hello.
Can you tell me if this is a false positive ? My Bitdefender keeps detecting the file media_plugin_cef.dll as a malware called Gen:Variant.Lazy.327720. Is that dangerous ? I've uninstalled SL and tried to reinstall it, but now I've got an error message about this dll. All that happened after the last update. Anyone else having this issue ? Is there sthing to worry about ? Thanks for your answers.