Hello - I'm getting this error when trying to use the Media Manager:

Invalid backend response.
Data is not JSON.
The most recent request was denied because it had an invalid security token. Please refresh the page and try again.

I'm running the most recent Joomla & K2 versions and have tried disabling error reporting but still get the message.
Any other recommendations would be appreciated!

^ Bump ^

Hi

I'm starting to get this error too and I'm on K2 v2.10.3
Any advice?

The only error I get is:
Missing: www.sawo.dk/da/administrator/css/theme.css

Regards
Thomas

Yes it does - and I have cleared the cache completely.

Thanks!
So it's the last line, that causes the issue?

 

I don't get more errors than the above mentioned, and that error I see on every site I make, but not the JSON error :-(

We get an invalid backend response when trying to access the MediaManager

The error happens in this request: /administrator/index.php?option=com_k2&view=media&task=connector&ff86b844a34b8546e70305cf82b5b429=1&cmd=open&target=&init=1&tree=1&_=1621427068790

Accessing this URL directly in the browser with an active admin session, responds with the following errormessage: "The most recent request was denied because it had an invalid security token. Please refresh the page and try again."

At the same time we get errors in PHP error log:
[19-May-2021 16:30:28 Europe/Copenhagen] PHP Notice: Trying to get property 'alias' of non-object in D:\wwwroot\components\com_k2\router.php on line 292
[19-May-2021 16:30:28 Europe/Copenhagen] PHP Notice: Trying to get property 'id' of non-object in D:\wwwroot\components\com_k2\router.php on line 316

Site is running on IIS 10, Windows 2019
PHP version: 7.4.16 NTS
K2 version: 2.10.3
Joomla version: Joomla! 3.9.26 Stable [ Amani ] 13-April-2021 15:00 GMT
MySql database version: 8.0.19

Please advise.