从outlook创建联系时出错

Question

当我打开表单创建新联系人时，我在动态365 for outlook中出现此错误：

生成此错误的代码如下：

var ctxt = Xrm.Page.context;
    var IDUser = ctxt.getUserId().replace("{", "").replace("}", "");
    var req = new XMLHttpRequest();
    req.open("GET", ctxt.getClientUrl() + "/api/data/v8.1/systemusers(" + IDUser + ")?$select=domainname,_businessunitid_value", false);
    req.setRequestHeader("OData-MaxVersion", "4.0");
    req.setRequestHeader("OData-Version", "4.0");
    req.setRequestHeader("Accept", "application/json");
    req.setRequestHeader("Content-Type", "application/json; charset=utf-8");
    req.setRequestHeader("Prefer", "odata.include-annotations=\"*\"");
    req.onreadystatechange = function () {
        if (this.readyState == 4 ) {
            if (this.status == 200) {
                var User = JSON.parse(this.responseText);
            }
        }
    };
    req.send();

此代码在表单的onload中调用，并且在Web表单中运行良好。

你知道我该如何解决这个问题吗？