Code

Reason

Explanation

0

Reserved

Normal working operation

1

Unspecific Reason

We don’t know what’s wrong

2

Previous authentication no longer valid

Client has associated but is not authorised.

3

Deauthenticated because sending STA is leaving (or has left) IBSS or ESS

The access point went offline, deauthenticating the client.

4

Disassociated due to inactivity

Client session timeout exceeded.

5

Disassociated because AP is unable to handle all currently associated STAs

The access point is busy, performing load balancing, for example.

6

Class 2 frame received from nonauthenticated STA

Client attempted to transfer data before it was authenticated.

7

Class 3 frame received from nonassociated STA

Client attempted to transfer data before it was associated.

8

Disassociated because sending STA is leaving (or has left) BSS

Operating System moved the client to another access point using non-aggressive load balancing.

9

STA requesting (re)association is not authenticated with responding STA

Client not authorized yet, still attempting to associate with an access point.

10

Disassociated because the information in the Power Capability element is unacceptable

11

Disassociated because the information in the Supported Channels element is unacceptable

12

Reserved

Not Used or Special Purpose

13

Invalid information element.

14

Message integrity code (MIC) failure

15

4-Way Handshake timeout

16

Group Key Handshake timeout

17

Information element in 4-Way Handshake different from (Re)Association Request/Probe
Response/Beacon frame

18

Invalid group cipher
or
Association denied due to requesting STA not supporting all of the data rates
in the BSSBasicRateSet parameter

*NEW*
The link speed requested by the client or AP is incompatible. (i,e. trying to
operate N only speeds on a G AP)

19

Invalid pairwise cipher

20

Invalid AKMP

21

Unsupported RSN information element version

22

Invalid RSN information element capabilities

23

IEEE 802.1X authentication failed

24

Cipher suite rejected because of the security policy

25-31

Reserved

Not Used or Special Purpose

32

Disassociated for unspecified, QoS-related reason

Quality of Service has denied the action.

33

Disassociated because QoS AP lacks sufficient bandwidth
for this QoS STA

34

Disassociated because excessive number of frames need
to be acknowledged, but are not
acknowledged due to AP transmissions and/or poor channel conditions

35

Disassociated because STA is transmitting outside the
limits of its TXOPs

36

Requested from peer STA as the STA is leaving the BSS
(or resetting)

37

Requested from peer STA as it does not want to use the
mechanism

38

Requested from peer STA as the STA received frames
using the mechanism for which a
setup is required

39

Requested from peer STA due to timeout

45

Peer STA does not support the requested cipher suite

45-65

Reserved

Not Used or Special Purpose

99

Typically “No Reason Code” / Unknown State

535

Reserved

Not Used or Special Purpose