In an attempt to start the form, an exception is made.

[shizuka]

Exception
This operation cannot be performed at the time of the change in the dimensions of the vehicle pole.
What's that pole and how do you expect to change the size of the column and start the uniform?

private void խումբ5ToolStripMenuItem_Click(object sender, EventArgs e)
{
    Group_5 newGroup5 = new Group_5();
    newGroup5.ShowDialog(this);//вот здесь дает исключение
}

[kalyn]

In the authorise, the hybrid fills it up to initialization, it doesn't work as far as I understand.

As a solution, what you think can be done https://stackoverflow.com/a/26628115/3768545 :

We add after. InitializeComponent(); The form of discontinuation of the authoressaise:

this.dataGridView1.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.DisableResizing;

In the method of loading GridWrapper_Load Turn it back on:

this.dataGridView1.ColumnHeadersHeightSizeMode = DataGridViewColumnHeadersHeightSizeMode.AutoSize;