Unexpected response from network

[Nemo1]

I am trying to set a divert from my O2 number to another number on another network, but when I try to set the divert I get the error message "unexpected response from network".

If I try to ring this number it connects fine but for some reason O2 wont accept a divert request to this number.

I should add that I have no problems setting a divert to any other number - it is just this one number I have problems setting a divert to. 

[MI5]

@Nemo1 

The only logical reason I can think of is a restriction on that number or the network it is on.

[Nemo1]

The number I am seeking to put the divert on (A) is on the O2 network and the number I am trying to set a divert to (B) is on the Id Mobile network.

The curious thing is that I can, from A, call and text B. It is just setting up a divert from A to B which does not work. 

[MI5]

Can you divert to any other numbers on ID or Three ?

[Nemo1]

Yes. No problem diverting to other numbers.

I should mention (just in case it is relevant) that number A is orginally an Orange (EE) number which as ported to O2 many years ago.

[MI5]

Well if you can divert to other numbers on that network there must be a restriction on that particular number, so I'd call CPW to check it.

[Nemo1]

Can I just check my understanding of how call divert works.

My assumption is that if I set up a divert from O2 number A to IDM number B that all O2 does when I set up the divert is to store number B in O2 somewhere. And that it is only when someone actually calls A that O2 would try to connect to IDM B and any error would become apparent. Is that right, or does O2 do some kind of check at the time when the divert is set up? (This is an "divert when unreachable" by the way).

[MI5]

The check will be made when the divert is setup to ensure the path is valid, t will be rejected.

[Nemo1]

Thanks for the explanation.

I did check with Id Mobile but they said it must be an O2 issue!

I suppose, if O2 checks the path upon divert set-up, logically it could be either O2 or IDM.

[MI5]

In this case, as you can set diverts elsewhere, I can't see it being an issue with O2.