Hi, I am using Ajaxuploader and it is mostly successful, but I am getting some errors for failed viewstate show below,  I am not on a farm, just a single web server database is seperate and I am not putting session in sqlserver. The server is a professional hoster and all mochine keys are set. Does someone have an idea of what this is?

thanks for any help

Server side exception, failed to upload dwa140_revB_linux_drivers_2130.zip


Debug Information:


System.Web.HttpException (0x80004005): Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that \x3CmachineKey\x3E configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster. ---\x3E System.Web.UI.ViewStateException: Invalid viewstate. \x0D\x0A      Client IP: 108.89.22.112\x0D\x0A      Port: 52523\x0D\x0A      Referer: http://www.shiftsmartspot.com/Submit/FileUpload\x0D\x0A      Path: /UploadHandler.ashx\x0D\x0A      User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.22 (KHTML, like Gecko) Ubuntu Chromium/25.0.1364.160 Chrome/25.0.1364.160 Safari/537.22\x0D\x0A      ViewState: /wEWAQUgQzpcV2luZG93c1xURU1QXEFqYXhVcGxvYWRlclRlbXB9zsJ6V51SAKhKUOM4ZOPJAdtUEjLBZLK3CU1CfABbdQ==\x0D\x0A   at System.Web.UI.ViewStateException.ThrowMacValidationError(Exception inner, String persistedState)\x0D\x0A   at System.Web.UI.ObjectStateFormatter.Deserialize(String inputString, Purpose purpose)\x0D\x0A   at CuteWebUI.b.a(String A_0)\x0D\x0A   at CuteWebUI.UploaderProvider.a(HttpContext A_0, IAjaxUploader A_1, Boolean A_2)\x0D\x0A   at CuteWebUI.UploadModule.e(HttpContext A_0)