I have read through all the guides and done all the tips and tricks (which incidently all refer to the same thing, shut down the iPad, put sim card in, enter the apn setting giffgaff.com, giffgaff, password).
I keep getting the stupid "could not activate mobile data network"
Shut down and reset the device many times to no avail.
Finally, just reset the settings and the iPad reverted to the o2 settings mobile.o2.co.uk, o2web, password and the settings work fine.
Is it OK to leave the APN settings onto the o2 settings for the long term? The iPads are being sent to a client to use and I do not want a callback with technical issues saying the mobile data suddenly stopped working.
I dont understand why the giffgaff.com apn will not work but the o2 settings work on the giffgaff sim card.