On various forums quit some users reported problems with internet sharing after cyan on L1520 and a few other Lumia's as well.
Encountered this issue as well (Vodafone Netherlands) but after fully entering the MMS settings internet sharing worked again. I'm almost 100 percent sure this wasn't required earlier since I never use MMS so don't even care to setup the account but never had issues with internet sharing. But with some networks it could be a requirement nowto get internet sharing working, worth a try for people with internet sharing issues after Cyan.
Encountered this issue as well (Vodafone Netherlands) but after fully entering the MMS settings internet sharing worked again. I'm almost 100 percent sure this wasn't required earlier since I never use MMS so don't even care to setup the account but never had issues with internet sharing. But with some networks it could be a requirement nowto get internet sharing working, worth a try for people with internet sharing issues after Cyan.
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