WiFi connections failing after update to 10.2.1

Question

good day,
after upgrading the OS to 10.2.1, my Q5 stopped connecting to networks already saved (and was working for a couple of weeks) or started behaving strangely:
On a WEP (yes i still use this) link on a D-link router, it would connect but not obtain IP addresses. setting the IP address manually does not solve the problem and the link stays limited although every other devise works: 2 iPhones, an iPad, 2 Samsung Android phones, an Asus TF101 Android tablet, a Win8 Laptop, a Win7 laptop, and a WinXP laptop (yes we still keep one of these).
On a WPA2-Personal AES link on a Netgear WNR1000, it will simply not authenticate at all although I double checked the password.
whats happenning? and how can I fix it?
by the way, i'm a CCNA studying into CCNP so I KNOW networking.
regards,

Answer 1

Hello,
Since what you request is downgrade (rather than trying to resolve the issue), here are two methods:
http://supportforums.blackberry.com/t5/BlackBerry-10-Smartphone/How-to-Reload-your-Blackberry10-OS/t...
http://supportforums.blackberry.com/t5/BlackBerry-10-OS-Device-Software/Upgrading-OS10-devices-using...
Good luck!
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