Error Upload file when this web was up host
I write a application to upload file and up to host :
http://www.buiductoan.somee.com/default.aspx
My code:
if (FileUpload1.PostedFile != null)
{
String filename = FileUpload1.PostedFile.FileName;
FileUpload1.PostedFile.SaveAs("C:\\"+filename);
}
I run success in local host but I run on http://www.buiductoan.somee.com/default.aspx has error :
Validation of viewstate MAC failed. If this application is hosted by a Web Farm or cluster, ensure that <machineKey> configuration specifies the same validationKey and validation algorithm. AutoGenerate cannot be used in a cluster.
And
Access to the path 'C:\Untitled.png' is denied.
Can you help me,please?