"There is a problem with this Windows Installer package." - Fix inside!

This might help. To begin, you can identify if you have any problematic programs causing the error. This is simple to do as the alerts will pop up every time you run the affected program. Once the faulty program has been determined, you have to remove it from your computer and re-install again to fix the problems with it. To delete programs from your system, you have to go to "Start" and then locate "Run". After that, type "appwiz.cpl" and then click "Enter". Next, you have to find and choose the program you want to delete from the list and then press "Remove" (for Windows XP) or "Uninstall" (for Windows Vista and Windows 7). Afterwards, reboot your computer. This process will remove the program from your PC. To re-install the program, you may download a new installation file from the internet or use an installer CD/DVD.

If after completing the above mentioned steps the error still persists, then you might have issues with your registry. The registry is a huge database where vital files, information, and settings are stored. Windows reads the files it needs to run programs smoothly through this database. Unfortunately, the registry gets damaged, corrupted, or clogged up easily, making Windows unable to access the required files in order for it to execute its operations. Once this happens, problems like the 0x000007b error occur all too often. To address this issue, download and run a registry cleaning program like the highly recommended CCleaner.

If using Win7 OS, remember to "Run as Administrator" while installing new program, I also advice to temporarily disable your AV/Firewall before installing new program.