I've seen this before with Commerce. What you can try to do is rename the app_themes folder in your web root.
In that folder you will find an icon for Commerce. Copy this icon to the CMS folder in program files (ex C:\Program Files (x86)\EPiServer\CMS\5.2.375.236\Application\App_Themes). It should lie in the same folder structure inside the App_Themes folder. Can't say what the folders are right now as I don't have a Commerce installation in front of me.
Then restart IIS and the problem should not appear again.
Thanks Toni. I will try that.
Add the below entries in web.config entries
Sometimes when i'm using the CMS of EpiServer i getting a strange layout (screenshot below) of the CMS. I can solve this by recycling the application pool in IIS or change the web.config and save it.
Does somebody has a solution for this problem?