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Error codes › EMM cause (LTE NAS)

EMM cause #25 Not authorized for this CSG

EMM cause (LTE NAS)3GPP TS 24.301 §9.9.3.9 and Annex A

What it means

Not authorized for this CSG: the subscriber isn't allowed in this closed subscriber group (femtocell).

Where you see it

In LTE NAS Attach reject, Tracking area update reject, Service reject or Detach request.

What to check

Look at the S6a (MME↔HSS) and S11 messages just before the reject: they usually show the real trigger.

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