Please help us help you and fill where relevant:
LimeSurvey version:6.10 // 6.15
Own server or LimeSurvey Cloud: Own
Survey theme/template: Fruity
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Hi there people, this time i have a weird issue, i have installed a Limesurvey on a dedicated server that was working and keep working as always, just now the icons have been missing, I attach one example .

The same happens with the logos on the main page.
 

And when I try to find the image, the image exist on the server but the error that gives me chrome is 403, like theres some permission bad.

 
Can someone help me to figure it out what happen? This yerterday was working good, today the icons dissapear.

I have a Windows 10 dedicated server, with a plesk with Limesurvey, I even give permissions to everyone to the folder tmp and assets, where is suppose to be that icons, at least the icons of the login page, i reboot the server and update limesurvey from 6.10 to 6.15.

Thanks for the help.

I respond myself, i be able to solve it, the problem was the firewall on my plesk, specificly Web Application Firewall (ModSecurity) the rule called (and is not a joke) "paranoia-level/2", deactivating it, the icons come back to his place.

Thanks for the help.