Cant edit any module

[MKI-Miro]

Hi

I am using 3.7.5 and everything worked fine. But suddenly I cannot edit any module. When i Click save, it doesnt save and it redirects me to module list without any error.

What should be wrong? or what should I do to describe error better?

Thanks

[MKI-Miro]

Edit:

No error message in console.
Same behavior for different users
Cleared Browser and Joomla cache

problem is still present

[imanickam]

Since you could edit the modules earlier in the same site, probably it is not a bug.

Couple of things to check:

(a) Check whether the anything has changed in the operating environment such as PHP version between when the modules could be edited and now

(b) Check whether any new extension has been added between when the modules could be edited and now

(c) In the Global Configuration for the option "Error Reporting" (tab Server, section Server Settings) set the value to Maximum and see whether any error is showing up

(d) Check the PHP error logs

(e) Check for any errors in the PHP log

[MKI-Miro]

b) Only Akeeba backup was updated from 5.5 to 5.6
c) tried but no error displayed

[MKI-Miro]

I found it on logs

PHP Warning: Unknown: Input variables exceeded 1000. To increase the limit change max_input_vars in php.ini. in Unknown on line 0, referer: index.php?option=com_modules&view=module&layout=edit&id=95

So i set max_input_vars to 5000 and not it works!

Thank you for hints