Next two options are to try a clean profile, or to reinstall Opera with a different profile. The latter can be done by changing the installation path in the installer. If you change the path you can also choose either a regular install or a "Stand-alone (USB)" install. For a regular install, the profile location is based upon the name of the folder, so using a different folder name (instead of the default "opera") will result in Opera using a clean profile. A stand-alone install always places the profile inside the program folder, so if doing a stand-alone install make sure the install location is someplace you will have access to without having to run as administrator all the time.
And if you just want to try a clean profile, rename Opera's current profile (while Opera is closed of course) so that Opera will create a new one.
If neither of those work, the error is somewhere else on your system - in the network setup or your firewall/security software probably.
Tks for your help:)
Unluckily it doesn't work...but finally I've found what had happened luckily
the OS I installed bundled several plug-ins and I've download the adwcleaner. Although this program deleted my online chating software but my perfect Opera came back
Tks for all who concerned this discussion !