Hi @BMCP , could you please share how did you configured MAVEN_OPTS? Have you tried something like (docs):
set MAVEN_OPTS=-Dhttp.proxyUser=user -Dhttp.proxyHost=host -Dhttp.proxyPassword=password
Please also take a look at this topic and tell us if you still can’t solve the problem (there is an approach with SONAR_SCANNER_OPTS there).