Hi,
this means that some of the name s is wrong check the values of the property Name of these this controls and see what is the difference
Best Regards,
Iordan

There's also another possibility - that the names are correct but the label and/or progressbar has not been placed directly on the form but is inside some container such as a panel or groupbox.
If that's the case, then you'll need to drill down into the container's Controls collection to find it.

Yes vulpes you ar right the progress bar is inside of a group box!
how can i access the item inside of group box?
thanks!
david

If it's inside groupBox1 say, then you can get to it as follows:
GroupBox groupBox1 = (GroupBox)thrd.Controls["groupBox1"];
ProgressBar progressBar1 = (ProgressBar)groupBox1.Controls["progressBar1"];
progressBar1.Value = 10;

Yes, vulpes it work's!
But now i get this error
Cross-thread operation not valid: Control 'progressBar1' accessed from a thread other than the thread it was created on.
any idea?
thanks

Hi,
This means that you are accessing the control from background thread.
There are few ways to avoid this if you are more spesific about your
situation i can tell you what is the best way to do it. One way is to use Control.Invoke();
Best Regards,
Iordan

Ok
I have a background worker that export same data to excel
i have a foreach that export row by row, inside of this i want to update the progress bar.
here is the code:
foreach (DataRow dr in dt.Rows)
{
for (int k = 0; k < cols; k++)
{
string cell = alfabet[k] + cellRow;
aRange = ws.get_Range(cell, cell);
string temp = dr[k].ToString();
cellCol++;
aRange.Value2 = temp;
}
progreessBar1.value = cellRow;

cellRow++;
cellCol = 1;
}
I have a background worker that call's the function and inside of the function is this foreach!
thanks

Hi, try this
//declare with the other variable int the from
delegate void MyDelegate(int a );
....
// in the foreach cycle put this
BeginInvoke(
new MyDelegate(MyMethod1),
new object[]{cellRow} );
//Declaration of method
void MyMethod2(int a )
{
progreessBar1.value = a ;
}
Best Regards,
iordan

it tells me:
BeginInvoke does not exist in the current context!
Thanks

It sounds like the code in question is not within a form but within a different class.
If the form reference 'thrd' is still in scope, I'd see if this monstrosity (albeit self-contained) will work:
thrd.BeginInvoke(new MethodInvoker(delegate(){progressBar1.Value = cellRow;}));