Export the certificate from your company’s Citrix web portal via your browser and manually import it into the Windows Certificate Manager (Trusted Root Certification Authorities) or macOS Keychain Access.
If you’re having trouble getting into your virtual desktop or apps, you aren't alone. (now mostly updated to Citrix Workspace app ) is the bridge to your work environment, and sometimes that bridge needs a little maintenance. citrix receiver troubleshooting guide link
Your local device is missing the root or intermediate security certificates utilized by your organization's Citrix NetScaler Gateway. The Fix: Export the certificate from your company’s Citrix web
Right-click tray icon > Troubleshooting > Collect Logs 0.5.1 citrix receiver troubleshooting guide link