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Sorry if this question has been asked before; if it has, I couldn't find it.
On 12.04 I'm able to connect to wi-fi and load pages on the internet, but I'm asked to reenter the wi-fi password every ten seconds. If I reenter it, it connects again just fine, but it asks again in about ten seconds, making the wi-fi essentially unusable.
I use a Lenovo ThinkPad SL510, if that matters. I never had a similar problem under 11.10.