If you need solution to uncompress your CPanel backup in tar.gz format, you can download 7zip. 7-Zip is a file archiver with a high compression ratio.
7-Zip is open source software. You can use 7-Zip on any computer, including a computer in a commercial organization. You don’t need to register or pay for 7-Zip. But you can make a donation to support further development of 7-Zip.
* Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
* Unpacking only: RAR, CAB, ISO, ARJ, LZH, CHM, MSI, WIM, Z, CPIO, RPM, DEB and NSIS
For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10 % better than the ratio provided by PKZip and WinZip