After installing (https://docs.wso2.com/display/DAS301/Installing+as+a+Windows+Service) and starting WSO2 DAS 3.0.1 as a windows service, there is an exception when opening page of view roles from users page as below,
Then popup blank page,
However, this error does not happen if I use wso2server.bat running in command console. The same issue happens to WSO2 AM 1.10.0 as well.
Cheers, Sean
Try adding below line to wrapper.conf
wrapper.java.additional.26 = -Dorg.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false
This is mentioned in Identity Server Docs. I reopened a WSO2 Document JIRA about this.