Technical Tip: WhatsApp 'Couldn't Download Image. Try again. If the problem keeps happening, turn off Wi-Fi or remove VPN, or connect to a different Wi-Fi network' error

[raksshaya]

Description	This article describes how to resolve the error message 'Couldn't Download Image. Try again. If the problem keeps happening, turn off Wi-Fi or remove VPN, or connect to a different Wi-Fi network, which may appear when attempting to download a document via WhatsApp.
Scope	FortiGate.
Solution	The error might occur after enabling the application control feature to allow WhatsApp. When application control is configured to allow all WhatsApp application signatures, it may still block certain secure URLs required during file downloads, irrespective of whether  SSL certificate inspection or deep inspection is enabled. In such cases, security logs will typically show a deny entry for root.Certificate.URL under Security Events > Application Control. To resolve this issue: Navigate to Application Control settings. Edit the existing application control profile associated with the WhatsApp traffic policy. Under Application and Filter Overrides, select Create New. Add an explicit rule to allow root.Certificate.URL as shown in the image below. From CLI : config application list     edit default   --> This will be the Application Control Profile name.         config entries             edit 0                 set application 41474                 set action pass         end end After allowing root.Certificate.URL, WhatsApp will download files without errors, and logs will show the URL as allowed. The error occurs because WhatsApp cannot establish a secure connection to download media due to SSL certificate inspection or blocking by a firewall, VPN, or content filter. When the root.Certificate.URL is being allowed, which permits or bypasses SSL inspection for WhatsApp's media servers. This enables WhatsApp to securely connect and download images without triggering SSL errors, resolving the issue.