Data at the root level is invalid. Line 1, position 1.

If you are experiencing the below error message when you are trying to perform an action in TM Master:

System.Xml.XmlException: Data at the root level is invalid. Line 1, position 1.

at System.Xml.XmlTextReaderImpl.Throw(Exception e)

at System.Xml.XmlTextReaderImpl.Throw(String res, String arg)

at System.Xml.XmlTextReaderImpl.ParseRootLevelWhitespace()

at System.Xml.XmlTextReaderImpl.ParseDocumentContent()

at System.Xml.XmlTextReaderImpl.Read()

at System.Xml.XmlLoader.Load(XmlDocument doc, XmlReader reader, Boolean preserveWhitespace)

at System.Xml.XmlDocument.Load(XmlReader reader)

at System.Xml.XmlDocument.Load(Stream inStream)

at Janus.Windows.Common.Layouts.JanusLayoutReader.a(Stream )

at Janus.Windows.GridEX.GridEX.LoadLayoutFile(Stream stream)

at TmUiTools.CtlUiGridEx.LoadGridSettings(GridEX grid, String settings)

at TmUiTools.CtlUiGridEx.SetSettings(String settings)

at TmMv2.CtlTmMv2DueList.InitGrid()

at TmMv2.CtlTmMv2DueList.InitCtrl()

at TmMv2.CtlTmMv2Due.Init(Boolean ShowSearchFields)

at TmMv2.FrmTmMv2Main.InitDue()

at TmMv2.FrmTmMv2Main.selectCtlFromExplorerBarItem(ExplorerBarItem item)

at TmMv2.FrmTmMv2Main.explorerSide_ItemClick(Object sender, ItemEventArgs e)

at Janus.Windows.ExplorerBar.ExplorerBar.OnItemClick(ItemEventArgs e)

at Janus.Windows.ExplorerBar.ExplorerBar.i(ExplorerBarItem )

at Janus.Windows.ExplorerBar.ExplorerBarItem.InvokeOnClick()

at Janus.Windows.ExplorerBar.ExplorerBar.OnMouseUp(MouseEventArgs e)

at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)

at System.Windows.Forms.Control.WndProc(Message& m)

at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)

at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)

at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Perform this action to fix the problem:
(Please note that this will reset the grid layouts to the default setting)

Go to My Place -> Preferences -> Grid -> Delete my user settings:

Restart TM and then try the same operation as when you got the error previously.