07-10-2026 04:25 AM
Hi
Actually i am working on 8510 WLC and suddenly I can't access the WLC via https nor http even though are enabled
I checked the certificate validity of webadmin it shows that expired 2024 but WLC time is 2022 amd actually also new access points not joining
Solved! Go to Solution.
07-13-2026 01:08 AM
- @Turki.A.Baqatada You can deploy and use the 9800-CL (virtual) controller without any licensing
complaints for up to 50 access points.
>....Join message decode Maximum message size Failed
You will get into compatibility problems if you let the access points use a
9800 controller and try to go back to an aireos controller with a too old
version
+ What error do you get in a browser when trying to use the GUI ?
M.
07-13-2026 02:59 AM
> so you this message Join message decode Maximum message size Failed means that it is comatibility issues du joined to 9800 ?
Yes - the CAPWAP version used by the new 9800 AP code is not compatible with 8.0.152.0.
You will need to manually install the 8.0.152.0 AP code (153-3.JA12) on each AP using TFTP:
https://software.cisco.com/download/home/285029865/type/280775090/release/15.3.3-JA12
Regarding the http/https: http does not require a certificate - probably just needs WLC reboot. https - regenerate the certificate and then reboot the WLC as advised in previous replies.
07-10-2026 04:28 AM - edited 07-10-2026 04:29 AM
- @Turki.A.Baqatada Post the full boot process of an access point that fails to join, if this happened
suddenly then try a reboot of the controller.
M.
07-10-2026 04:41 AM
Actually now I want to resolve web access first that will helps me alot
My question that if the validity of web admin certificate expired on 2024 and I configured the time to be on 2022 which right now configured will bypass this issue or not and if not what could be the solution
07-10-2026 04:47 AM
@Turki.A.Baqatada Try regenerating the certificate as I suggested.
07-10-2026 04:58 AM
@Turki.A.Baqatada A very important detail I forgot to mention, when generating a new certificate, it is necessary to restart the WLC.
07-10-2026 04:47 AM
@Turki.A.Baqatada >....Actually now I want to resolve web access first that will helps me a lot
What error do you get in a browser when trying to use the GUI ?
M.
07-10-2026 04:29 AM
07-10-2026 04:32 AM
Oh, and also correct the date and time of your WLC.
07-10-2026 04:36 AM
@Turki.A.BaqatadaJust a heads-up, are you aware that this controller model is no longer supported? You should consider migrating to a C9800.
07-10-2026 04:38 AM
Yes I know and we are going to move soon
07-11-2026 02:25 AM
@Turki.A.Baqatada Have you rebooted the WLC for a start?
You should be using the final release of code 8.5.182.12.
> new access points not joining
Read through all the relevant Field Notices in my signature below - make sure you follow all the steps required to resolve them (disable NTP and set time back is only 1 step of many).
What model are the new APs?
Collect the complete console log from an affected AP from power on, save to a text file (.txt) and attach here for us to see what the AP reports.
What do these commands on WLC CLI (no GUI needed) show?
show ap join stats summary all
show ap join stats summary <ap-mac>
07-13-2026 12:19 AM
@Rich R actually let my explain you the full picture here
first of all we are installing 9800 as a demo and for testing we installed AIR-CAP3702I-E-K9 airos APs to check if it is going to join and joined successfully but now due no license we want to return thes APs to join our old 8510 WLC version 8.0.152
What model are the new APs?
AIR-CAP3702I-E-K9
show ap join stats summary <ap-mac>-
Reason for last unsuccessful join attempt................ Join message decode Maximum message size Failed
_____________________________________________________
Second issue that we are facing and tried alot of things which is i can't access gui
show time
Time............................................. Tue Jul 12 11:47:15 2022
web admin certificate
Start : 2014 Apr 23rd
End : 2024 Apr 23rd
for AP logs
access point in remote site and can not provide now
07-13-2026 01:08 AM
- @Turki.A.Baqatada You can deploy and use the 9800-CL (virtual) controller without any licensing
complaints for up to 50 access points.
>....Join message decode Maximum message size Failed
You will get into compatibility problems if you let the access points use a
9800 controller and try to go back to an aireos controller with a too old
version
+ What error do you get in a browser when trying to use the GUI ?
M.
07-13-2026 02:10 AM
What error do you get in a browser when trying to use the GUI ?
Secure connection failed
so you this message Join message decode Maximum message size Failed means that it is comatibility issues du joined to 9800 ? if so what can we do to resolve this issue and let them join 8510 WLC ? do i have to hard reset APs
07-13-2026 02:59 AM
> so you this message Join message decode Maximum message size Failed means that it is comatibility issues du joined to 9800 ?
Yes - the CAPWAP version used by the new 9800 AP code is not compatible with 8.0.152.0.
You will need to manually install the 8.0.152.0 AP code (153-3.JA12) on each AP using TFTP:
https://software.cisco.com/download/home/285029865/type/280775090/release/15.3.3-JA12
Regarding the http/https: http does not require a certificate - probably just needs WLC reboot. https - regenerate the certificate and then reboot the WLC as advised in previous replies.
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