Windows 8 Default or NEW Apps not update nor install

[WhizzKidRaJ]

"Something happened and this app wasn't installed. Please try again. Error code: 0x80073cf9".
Screenshot - http://img233.imageshack.us/img233/3365/appsc.jpg

System Information generated from msinfo32.exe - http://pastebin.com/Ruq43tdc

Windows Activated on Nov 2, 2012 and installing MS updates and Office 2013 updates from then and no problem in it.
Only this apps problem. 1 month before my brother had also tried to install some free apps and got this error but he ignored it. Now today I tried to install Dropbox
Please help
I google the problem also but some said to use WSReset.exe in run or disable or uninstall my ANtivirus i.e Avast, WSReset.exe cleared cache refreshed then tried again to install apps but same problem
and I don't want to uninstall Avast as my other friends using windows 8 pro with media center also use avast and they don't have this problem so I didn't tried this. Because here
http://answers.microsoft.com/en-us/windows/forum/windows_8-windows_install/windows-8-apps-not-working/01014156-fee4-4cbe-9744-47c8e07b3314?page=4&tm=1357817202533
the 5th post suggest to uninstall avast as it fixed that guys problem.
So I decided to post it here and let u know about this if there's some bug please reply and fix it and I'll wait for ur next program update.
Thanks

[schmidthouse]

I see the 3rd. post in the link you supplied suggests "Refreshing my PC".
Have you tried this option?

[WhizzKidRaJ]

Ok reinstalling windows 8 since I discovered 1 more huge problem than this apps problem i.e I cannot browse but yes can connect to internet after installing a third party firewall. With windows firewall no such problems. So far I've tried AIS and Emsisoft IS both of their firewalls when stopped or disabled also I still had the same problem. Only uninstalling the whole security suite solved the problem so this has forced me to do a clean install of win 8 pro and will report back here after the install and see whether both apps and firewall-internet issues are fixed. Please pray that my problems gets solved after this clean install

[CraigB]

Why don't you just refresh the PC rather than clean install - charms bar/settings/change pc settings/ general/refresh pc it'll save a lot of extra work.

[WhizzKidRaJ]

tried that sir it says some files missing please insert the windows dvd not technically correct words by me but files missing and insert windows recovery disk also this firewall and internet issue has arisen now giving me two headaches at a time and I have googled for such problems but unsuccessful in resolving these two problems so I'm like now cannot think of anything but clean install as that always guarantees the problem to be solved. If only apps problem was there then I wouldn't have done it but yesterday after posting this thread i discovered another fatal problem of this firewall-internetthing so I cannot take it now as I posted this problem in many forums and all of them are saying do this OK not worked for u then do that. No single straight answer only guesses and u cannot expect every user to be knowing to follow all such instructions which they have given on social Microsoft forums since many of the users might be of beginners level like my elder brother who has forced me to do this clean install as he is senior.

[CraigB]

Sounds like that be your best route then, have fun

[WhizzKidRaJ]

problem solved after clean install of windows 8 pro. Thank u 2 all for the replies and helping me

[CraigB]

We weren't much help, glad that you solved your problem though