From the forums I have read, this seems to be an existing bug in Visual Studio. I recommend that you manually write out the code in your "Form.Designer.cs". You will have to enter your respective code appropriately and then your column will automatically appear in your DataGridView without the "Column is not a valid identifier" issue that appears when using the Graphical User Interface.

Form.Designer.cs

/// region Component Designer generated code

/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>

private void InitializeComponent()
{
this.YourColumnName = new System.Windows.Forms.DataGridViewTextBoxColumn();
this.dataGridView.Columns.AddRange(new System.Windows.Forms.DataGridViewColumn[] {
this.YourColumnName
});
//
// YourColumnName
//
this.YourColumnName.HeaderText = "Your Column Name";
this.YourColumnName.Name = "YourColumnName";
this.YourColumnName.ReadOnly = true;
//
}

///endregion
private System.Windows.Forms.DataGridViewTextBoxColumn YourColumnName;