Event 6273 · Reason Codes 48 & 49
NPS Reason Code 48 vs 49 — which policy layer rejected you
Both codes say “nothing matched,” and they get confused for each other constantly — but they point at different policy layers, and troubleshooting the wrong layer wastes hours. NPS processes every request through two gates, in order:
RADIUS request
│
▼
1. Connection Request Policies (CRPs) → none matched? ── Reason 49
"does this server handle this request, and how?"
conditions: NAS address, port type, day/time, username realm
│
▼
2. Network Policies → none matched? ── Reason 48
"is this user/device allowed on the network?"
conditions: groups, auth methods, NAS port type, ...Reason 49 — rejected at the front door
No Connection Request Policy claimed the request. Credentials, group memberships, and network policies were never consulted — don’t touch them.
Look at how the request arrived: NAS IP, port type, time of day, username realm. The most common cause is the default catch-all CRP (“Use Windows authentication for all users”) having been deleted, disabled, or reordered during a cleanup. In proxy setups, it’s a realm that no forwarding rule covers.
Full write-up: Reason Code 49
Reason 48 — rejected at the second door
A CRP matched fine; no Network Policy did. Now it is about who is connecting: the account isn’t in the policy’s AD group (or is the wrong object type — computer vs user), a condition like NAS Port Type = Wireless doesn’t match what the NAS sends, or a broader policy higher in the list swallowed the request.
Full write-up: Reason Code 48
Tell them apart in the event itself
Open the 6273 event and read the Authentication Details:
| Field | Reason 49 | Reason 48 |
|---|---|---|
| Connection Request Policy Name | - (nothing matched) | a real policy name |
| Network Policy Name | - (never evaluated) | - (evaluated, none matched) |
That first field is the discriminator: if a CRP name is present, you’re past layer 1 — work the network policies. If it’s -, stay at the CRP layer no matter how suspicious your group memberships look.
One habit that prevents both
After any policy change, take one known-good and one known-bad request and walk the two lists top-to-bottom asking “would this match?” — NPS is strictly first-match-wins at both layers, and almost every 48/49 mystery is an ordering or condition literalism problem, not a Windows bug.