This error is usually caused by the antivirus/firewall interference.
Make sure that there is no antivirus/firewall software on the machine or its network environment preventing connections to/for:
TCP ports:
- 80
- 443
Addresses (the first four of them are storage specific - choose the ones you use):
- *.s3.amazonaws.com (full list of endpoints can be found here)
- *.microsoft.net
- www.googleapis.com
- api.backblazeb2.com
- mspbackups.com
Executables:
- CloudBerry Backup.exe
- Online Backup.exe - name can change if you are using rebranded software
- CBBackupPlan.exe
- Cloud.Backup.Scheduler.exe
- cbb.exe