This code is executed by many way. When it\'s executed by the form button it works (the button start a thread and in the loop it call this method = it works). BUT it doesn\'
You need write this:
if ( this.form.InvokeRequired ) { this.form.Invoke( ...... ); return; } this.form.Size = new Sizte( ... );
OR
if ( this.form.InvokeRequired ) { this.form.Invoke( ...... ); } else { this.form.Size = new Sizte( ... ); }