Compatibility of adblockplus with Norton

[phidaroma]

Hello,
I installed Adblockplus a few days ago and, since, Norton-antivirus is not allowed to check the system and install new antivirus.
If I put adblockplus off, Norton is ok again.
How can I do to keep norton-antivirus and adblockplus functions? I use adblockplus for Mozilla Firefox 38.0.5 and my computer is with windows 8.1
Thank you for help
Danièle

[mapx]

It can't be any connection between a firefox addon and a standalone program like norton. Or are you talking about some addon norton (anti banner) added in firefox ?