The Blizzard Battle.net desktop app can't verify necessary data. Follow the steps below to resolve the problem.
- Go to https://www.digicert.com/digicert-root-certificates.htm
- Find DigiCert Assured ID Root CA and click Download
- Double-click DigiCertAssuredIDRootCA.crt and click Open
- Click Install Certificate...
- Select Local Machine and click Next
Note: If a User Account Control dialog box pops up, click Yes
- Select Place all certificates in the following store and click Browse
- Select Trusted Root Certification Authorities and click OK
- Click Next
- Click Finish
If this doesn't resolve your issue, please ensure that your computer's clock has the correct Date and Time settings for your location. If they do not match, you may get encryption or verification errors.