Google play and web navigation are OFF in 3G network

[vaiadubai]

Hi,
since yesterday I have this problem with Android 2.3

The problem occurs only in 3G network, not in Wi-fi.

I can browse the apps in Google play but, when I choose it,
the download bar is stuck at zero bytes.
Even the web navigation is OFF using Dolphin browser.
Strange to say, but other applications like Youtube or radio streaming
go very well.

I have a suspicion: I installed applications like "ProxySettings"
or "Autoproxy lite" and then I uninstalled them.
Do you think they could take me some wrong hidden setting?

Or my problems come from Download manager?
How can I be sure it is working fine?

I am starting to have no ideas.....
Thanks for support!