unable to paste data in the same work sheet in excel 2007

I've been using this worksheet since January 2014 and never came across such issue. Whenever the data in a row is copied (it appears to be copied shown by the dashed line around the selected data) and pasted in another row, the new row(destination) remains empty. The dashed line around selected data also disappears as iff the data is copied in normal instances.
This sheet is linked to another excel sheet on the same PC. The other sheets on this PC are working fine. The problematic sheet holds almost 7000 rows and 30 columns of data.
The problem stated is occuring with unlinked cells (not the linked ones).
I've reinstalled the software and also changed the destination folder of the sheet, but all in vain.
Any solution ?

Sorry acroley1, I cant post the workbook. Although, the item being copied are using relative references.