As you did ask for the code and marked your own answer as the solution, you could at least have posted the code on how to create a package action ;-)

Otherwise this topic won't have any use for others searching for a solution.

That would be helpful wouldn't it.

        public static bool Install()
    {
        try
        {

            bool result = false;

            var document = new XmlDocument();
            document.PreserveWhitespace = true;

            document.Load(HttpContext.Current.Server.MapPath(FULL_PATH));

            bool modified = false;

            var rootNode = document.SelectSingleNode("/settings/scheduledTasks");

            bool insertNode = true;

            //<task log="true" alias="ContentReviewReminders" interval="60" url="http://localhost:17479/backoffice/RemindersApi/ContentReviewReminders/getDetailsForReviewEmail" />

            if (rootNode.HasChildNodes)
            {
                // Look for existing nodeType nodes
                var oldNode = rootNode.SelectSingleNode(string.Format("task[@name = '{0}']", "ContentReviewReminders"));

                if (oldNode != null) oldNode.ParentNode.RemoveChild(oldNode);

                var node = rootNode.SelectSingleNode(string.Format("task[@name = '{0}']", "ContentReviewReminders"));

                // If name already exists 
                if (node != null)
                {
                    // Cancel insert node operation
                    insertNode = false;
                }
            }

            // Check for insert flag
            if (insertNode)
            {
                string domain = HttpContext.Current.Request.IsSecureConnection ? "https://" + HttpContext.Current.Request.Url.Host + (HttpContext.Current.Request.Url.Port) : "http://" + HttpContext.Current.Request.Url.Host + (HttpContext.Current.Request.Url.Port > 0 ? (":" + HttpContext.Current.Request.Url.Port) : "");

                string domainAndPath = domain + "/backoffice/RemindersApi/ContentReviewReminders/getDetailsForReviewEmail";

                // Create new node with attributes
                var newNode = document.CreateElement("task");
                newNode.Attributes.Append(XmlHelper.AddAttribute(document, "log", "true"));
                newNode.Attributes.Append(XmlHelper.AddAttribute(document, "alias", "ContentReviewReminders"));
                newNode.Attributes.Append(XmlHelper.AddAttribute(document, "interval", "60"));
                newNode.Attributes.Append(XmlHelper.AddAttribute(document, "url", domainAndPath));

                // Append new node at the start of root node
                rootNode.PrependChild(newNode);

                // Mark document modified
                modified = true;
            }

            // Check for modified document
            if (modified)
            {
                // Save the Rewrite config file with the new rewerite rule
                document.Save(HttpContext.Current.Server.MapPath(FULL_PATH));

                // No errors so the result is true
                result = true;
            }

            return result;
        }
        catch
        {
            return false;
        }


    }

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