google mail not syncing

[crish]

I switch off Data Sync to save battery life, but today google mail will not sync, just keeps coming up with an error message..the others will sync.
I've switched phone off and on, tried all day but cant get it to work.
My market and internet connectivity are also affected.

Help!
Thanks

 

[nx1977]

Ensure your time and date are correct (especially the year), and disable auto update of date and time.

 

[crish]

Done. They were fine.
Cant access 'manage Applications' either,it just hangs in the loading page..