WinRAR reports CRC error

Hi

WinRAR reports CRC error while extracting the tar.gz file:
------------------------------------------------
C:\...........\Downloaded-Modules\seo_checklist-5.x-1.3.tar.gz: CRC failed in C:\...........\Downloaded-Modules\seo_checklist-5.x-1.3.tar.gz. The file is corrupt
------------------------------------------------
My WinRAR is ver 3.20. It extracted files into directory, error message came after extraction.

I tried WinZIP ver 8.0 and extracted it without error messages. I compared 2 directories - they are NOT the same size. I downloaded the file with Firefox, IE and Opera - the same CRC error in WinRAR. This was not happened to me before with other Drupal modules.

Arieh