Forms.Timer start & Threads

I've got an incrementTimer()-Function, which is called on mous click.
It increments Windows.Forms.Timer interval and starts the timer... No
problem so far.

Now I want to do the same when IR-remote button is pushed. Therefore
I've got a component in my project, which fires an event when user
pushes the button on his control. No problem so far either.

When I get the event from the remote, I start incrementTimer-Function
in exactly the same way as when mouse button is pushed (just calling
incrementTimer())

The first problem was, that an update to textBox.Text inside
incrementTimer() wasn't threadsafe anymore, but I solved this
following msdn instructions exactly:

// This delegate enables asynchronous calls for setting
// the text property on a TextBox control.
delegate void setButtonTextCallback(string text);

// If the calling thread is different from the thread that
// created the TextBox control, this method creates a
// setButtonTextCallback and calls itself asynchronously using
the
// Invoke method.
//
// If the calling thread is the same as the thread that
created
// the TextBox control, the Text property is set directly.
private void setButtonText(string text)
{
// InvokeRequired required compares the thread ID of the
// calling thread to the thread ID of the creating thread.
// If these threads are different, it returns true.
if (this.button.InvokeRequired)
{
setButtonTextCallback d = new
setButtonTextCallback(setButtonText);
this.Invoke(d, new object[] { text });
}
else
{
this.button.Text = text;
}
}

the text updates perfectly, but my problem is that I do not receive
any Timer_Tick events anymore, although there is a call to
timer.Start() inside incrementTimer() and with mouse click it works
perfectly.

Very upset by this... please help