Repeat Header / Keep Header Visible in Tables in RS 2008

You selected "Repeat header rows on each page" or "Keep header rows visible while scrolling" in the tablix properties dialog, but it doesn't seem to work as expected? You might want to try the following four steps if you are using a "table"-style layout:

1. in the grouping pane, click on the small triangle and select "Advanced Mode" to show static members:
   
   
2. verify that you have the properties grid turned on (in BI Development Studio use F4, in Report Builder go to the "View" tab and select "Properties")
   
3. select the corresponding (static) item in the row group hierarchy
   
4. in the properties grid:
   - set KeepWithGroup to After
   - set RepeatOnNewPage to true for repeating headers
   - set FixedData to true for keeping headers visible

Reference link: