Can any one tell how to install the extensions called
MageBackup - Backup Solution Lite.....
After getting extension key i can't paste into mytheme....pls help...
What do you mean paste into your theme? It is a backup program. Nothing is suppose to be in your theme.
Also, just a FYI. Any Magento host would be making nightly backups and scheduled backups are built into Magento in the later versions.
Here is a link to the product support
http://magebackup.com/#support
