Due to the ever-evolving nature of Opera, many settings in the profile\opera6.ini file change not only in their values but their syntax and semantics as well. Failure to use a well-formed preferences file can cause all sorts of problems; starting with weird page loading, bad CPU and memory usage and so on.
If you think doing a clean install and migrating all your settings and mail over is a big task you are not feeling up to, the simple procedure below may give you enough of what you need. As always, remember to make a full back-up of your Opera profile and mail folders before doing this.
- As described above, note the location of your profile\opera6.ini file.
- (Optional) Run Tools > Delete private data to clear your cache and cookies.
- Close Opera completely.
- Delete the profile\opera6.ini file.
- Start Opera again.
You will lose the customizations you had made by directly editing the profile\opera6.ini file, of course -- and this is mostly a good thing (they are what probably landed you in this mess to start with). In Opera 9, you should be using opera:config instead of editing this file by hand, anyway. You will also lose the personal information you had entered in Tools > Preferences > Wand > Personal information, but it is easy enough to enter again.