I was trying to set up a VPN connection and it asked me about medium and high level security and a password which I didn't understand well! I failed to use VPN but now each time I try to unlock the phone, it asks for that password/pin. I removed the created VPN connection to get rid of it but to no avail. How can I remove this pin request?
If none of the other posted methods work, try the following solution, which solved this problem for me.
Open Settings and then navigate to
More and then
Security and tap
Clear Credentials. After that you can navigate to
My Device and then
Lock Screen where you can change the screen lock to whatever you desire.
I'm not sure what other credentials it clears besides the screen lock but I haven't found anything so far.
I've tested this on a Samsung Galaxy S4 running Android 5.0.1. The exact locations and names of different settings may be located in different places depending on your device.
Hope this helps.