0x80070057Invalid data has been used to update the list item. The field you are trying to update may be read only. In SharePoint

<nativehr>0x80070057</nativehr><nativestack></nativestack>Invalid data has been used to update the list item. The field you are trying to update may be read only. in SharePoint

Solution:-
Item["Title"] = "Test";

don't use Item["LinkTitle"]. this is readonly field.

Thank You.

Upload Documents to Document Library using file upload control in SharePoint

In Aspx page:-

------------------

<asp:FileUpload runat="server" ID="FileUpload1"></asp:FileUpload>

<asp:ImageButton runat="server" ID="imgbtnUpdateAttachment" OnClick="fileUpload_Click"

ImageUrl="../SiteAssets/Buttons/update_attachement.png"></asp:ImageButton>

In Aspx.cs Page:-

---------------------

protected void fileUpload_Click(object sender, EventArgs e)

        {

            if (FileUpload1.HasFile && FileUpload1.PostedFile != null)

            {

                SPSecurity.RunWithElevatedPrivileges(delegate()

                {

                    SPSite site = SPContext.Current.Site;

                    SPWeb web = SPContext.Current.Web;

                    string DocumentLibName = "Test Temp Documents";

                    web.AllowUnsafeUpdates = true;

                    if (FileUpload1.PostedFile != null)

                    {

                        Stream fStream = FileUpload1.PostedFile.InputStream;

                        byte[] content = new byte[fStream.Length];

                        fStream.Read(content, 0, (int)fStream.Length);

                        string Filename = FileUpload1.FileName;

          string destUrl = SPContext.Current.Site.Url + DocumentLibName + "/" + Filename;

                        SPFile spfile = web.Files.Add(destUrl, content, true);

                        spfile.Item["DocID"] = "1234567";

                        spfile.Item.Update();

                        fStream.Flush();

                        fStream.Close();

                        fStream.Close();

                        fStream.Dispose();

                    }

                    else

                    {

                        throw new FileNotFoundException("File Not Found");

                    }

                    web.AllowUnsafeUpdates = false;

                });

            }

        }

-----------------------------------------------------------------

Thank You