www programming

i have in hand, due to a little work, a wp with +- 16000 files of plugins, so as curious i've download and install locally to test out ...
test: on my localhost ... that should be magic so, unfortunately all working ... with all plugins, all activated. All working fine. There are about seo, login, group management plugins ... all working fine. On online site, login frontend NOT working. Looking ...
Not excluded that can be a single thing, that will resolve the two.

I had "to many redirects" again. I noticed painful loading ... somewhere something hindering or confusing each other

Google Chrome issues:
- sometimes on login (widget) i don`t see that i`m logged in or i`m logged in and redirected to real folder forum.. back, refresh => suddenly all seems ok
- last night i leave site... zzZZz , this morning "to many redirects"... clear cookies and site is loaded but loggin/loggout is buggy as i said above.

I`m going to test all with new browser - Firefox:
- login at homepage => page reloaded, login fields form widget are still here and i see that i`m not logged in. Refresh the page, now i`m logged in (i have logout on my login/logout widget). Strange.
- logout at homepage => not logged out, can`t logout... refresh page not help. I`m logged in.
- logout from Forum (iframe) - I`m logged out and redirected to homepage
This is reproduced every time at login/logout.
In meantime, again, as i said above "I noticed painful loading ... somewhere something hindering or confusing each other" and Mozilla Firefox give me this very crazy message :


Plugin is updated at 1.3.0.

retesting all as soon i can ...

using firefox and chrome for any test as main.
This happen on online site i imagine.
Can you setup an account that i can try out this, username/pass, so i can try to understand where is the problem since i can't at moment reproduce?
I've try all steps but nothing at moment. With what user this happen?