The settings for the Wait for FortiSandbox scan result before allowing file access and Timeout seconds options affect when the popup displays. See Configuring Sandbox Detection.
As FortiSandbox scans and releases files, a popup displays to inform you. You can view the recent scans by clicking the View recent scans option.
When FortiSandbox detects a virus and quarantines a file, the Virus Alert window displays.
You can use the Virus Alert window to view information about the recently scanned files by clicking the View recently detected virus(es) option.
With the information expanded, you can select a quarantined file and click the Restore button to restore the file.
Endpoint users can only restore quarantined files with FortiClient in standalone mode.