Error in proxy URL. Must be HTTP error in Ubuntu

export "http_proxy=user:pass@http://10.107.1.252:8080/"

I have also tried different combinations by playing quote marks and etc. Then I found out the correct syntax should be like below, the key here is the http:// before username as we use is to pass user/pass while opening URLs in browsers;

export http_proxy="http://domain\\user:password@10.107.1.252:8080"

if you want to make it permanent you can add that line to your etc\environment file. You can also check environment variables by running the export command directly or running export | grep "proxy" command to filter values with "proxy