Google apps losing connection to the servers when on mobile data I'm struggling with a weird connection problem I have with Google Maps 6.14.1 (#6140011) on the Galaxy Nexus (running Android 4.1.2/CM10).

The problem comes with the following symptoms when on mobile data:


The app stops loading additional tiles from the network that haven't previously been cached (while displaying cached ones without any problems).
The app no longer synchronizes starred places.
Whenever trying to calculate transit directions, it gets stuck on the "Getting transit directions" progress dialog (there is no error message, the dialog just stays there forever).
When trying to find a location (any search query), it gets stuck on the "Searching for: X" progress dialog (there is no error message, the dialog just stays there forever).
When switching to navigation, it gets stuck on the "Getting driving directions" progress dialog.


Things I've tried:


Rebooting: has no effect whatsoever.
Switching to wi-fi. Then everything works. This might make it sound like my network provider (a T-Mobile US MVNO) is blocking Google Maps traffic, but read on!
Tethering my tablet (CM9) to the phone: Google Maps works fine on the tablet, leading me to the conclusion that it's not the network blocking certain kind of data. However, when putting the SIM card directly into the same tablet, it again doesn't work.
Stopping the process, then clearing all data: this fixes this issue "for a while" (a few minutes to a few hours). I haven't yet figured out what causes the problem state to come back. It could be a fixed amount of time, it could be the first switch from mobile data to wi-fi and back, I don't know. UPDATE: I've had it happen 5mins after a 'clear data' with wi-fi all the time disabled, so the next connection to wi-fi does not seem to be the trigger.
Connect ddms: Getting transit directions does not cause any warnings or errors to be logged.
Reinstalling Google Maps: same as 'clear data', it helps for a few minutes.


Potentially related problems:


Gmail doesn't load any images. Other than that Gmail works perfectly, including background syncing e-mails on mobile data. This problem also occurs when on wi-fi.
Goggles always says "Network error" and "Authentication failed" (again, it works fine while on wi-fi).
Google Now reports "Requested content '…' cannot be accessed. Access is not allowed for this user agent."
In GMaps -> Settings -> About -> Network, I see the following error "Error - Bad HTTP response code: 403 for 62,71,72 class java.io.IOException". I can't get any additional information for this however. It might be weeks old, as I see this even while everything works perfectly fine.
Some things in the Facebook app work (notifications are shown), but some just lead to a "cannot find secure connection" error message (navigating to an individual post).
Other apps using the WebView control in some cases do not show content properly. (NewsRob for example can synchronize just fine, but when trying to switch to the web view of an article that was not previously cached, it shows an error message similar to the one of Google Now above.)


Further notes:


The mobile network indicator is blue/green during all of this (indicating a working connection to the Google servers) and everything else seems to work perfectly.
This has happened on various builds, including the CM10 final, installed from a factory reset.
This turned out to actually be a network provider problem (in my case: SimpleMobile in the US) and the fix is incredibly simple: remove the proxy server from the APN and everything works.

The final hint I needed was the Google Now error message, googling that took me to this thread on xda-developers.

I have no explanation for why 'clear data' fixed the issue for a few minutes and why this didn't occur when tethering the tablet through the phone (maybe a cached server connection somehow?). It does however explain why the problem occured again when putting the SIM card into the tablet (the APN comes with the problematic proxy as a preset), and that should have tipped me off, I guess.