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Bullguard blocking CORS preflight requests

Posted 12/29/2021 3:41 PM
User avatar

Stefan Richter Member

Date Joined Dec 2021
Total Posts: 1
Hello there,

I'm writing on behalf of two mutual customers. My company provides an online tutoring platform and two of my customers, both Bullgiard customers, are having problems connecting to it. 

Both have confirmed that the issue only surfaces on the machines that run Bullgoard, other machines on the same network work fine.

I'm attaching a screenshot of the problem. A CORS preflight requests apparently gets redirected by Bullguard which causes it to fail. This in turn prevents our web app from completing the authentication process. 

Do you have any tips? 

One customer managed to work arouynd this in MS Edge by turning Bullguard off, however Chrome still failed. The other customer turned Bullgoard off and only uses Chrome where it also still failed. 



Posted 1/5/2022 4:38 PM
User avatar

Andreea-Luciana Ostache Advanced member

Date Joined Nov 2016
Total Posts: 892
Hello Stefan,

Happy new year!

It would be great if the users could contact our support department, so we can get their BullGuard logs and accurately advise, but if I were to make an educated assumption about what could be done it would be that the customers need to add the site as an exception in Antivirus > Advanced Settings > Safe Browsing
Andreea-Luciana Ostache
Support Team Leader

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