Sitecore WFFM forms give 'The required anti-forgery cookie "__RequestVerificationToken" is not present.' error for Chinese site only

Question

We are using WFFM module in sitecore for creating forms. Forms work fine in all languages except Chinese. In case of Chinese site, all WFFM forms give following error-

Message: The required anti-forgery cookie "__RequestVerificationToken" is not present.

Source: System.Web.WebPages at System.Web.Helpers.AntiXsrf.TokenValidator.ValidateTokens(HttpContextBase httpContext, IIdentity identity, AntiForgeryToken sessionToken, AntiForgeryToken fieldToken) at System.Web.Helpers.AntiXsrf.AntiForgeryWorker.Validate(HttpContextBase httpContext) at Sitecore.Forms.Mvc.Controllers.Filters.WffmValidateAntiForgeryTokenAttribute.OnAuthorization(AuthorizationContext filterContext) at System.Web.Mvc.ControllerActionInvoker.InvokeAuthorizationFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor) at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName)

Web Forms for Marketers: an exception 'The required anti-forgery cookie "__RequestVerificationToken" is not present.' has occured while trying to execute an action ''

How do we fix it? Any help is appreciated.

Answer 1

For some reason, the redirect from http to https stopped working in our site. Due to this, antiforgery token was not sent to server in httprequest.cookies. Hence the WFFM forms stopped working and the error for missing token started appearing in logs.