For someone who is suffering "another version of this product is already installed' error

[MRoKHAOS]

I wanna back to BnS for Warlock but i can't reinstall due to this problem'another version of this product is already installed....try to configur or remove.....XXXXX(regedit keys)...'.

I googled hours and deleted all the files, regedit keys and this shit still there.

And finally i got the cure after the last try of hours search at Korean BnS website(google translate of course)-_-||||

There is a program developed by Microsoft called "windows installer cleanup utility". Even though the original one has been shut down but here is a new version called 'program installed or uninstalled trouble shooter' here is the link: https://support.microsoft.com/en-us/mats/program_install_and_uninstall  simply click 'run now' and follow the instruction it will fix the old BnS shits . 

General steps:

1.click--detect problems and apply the fixes for me(Recommended)

2. It will ask'Are you having a problem installing or uninstalling a program?' Click 'Uninstalling'(because in my opinion the base problem is the old BnS file cannot be 100% uninstalled so the new installing application just *cricket*ed up)

3. There is a list shows up and you need to find and select 'Blade and Soul' and click next.

4. It will ask'Blad and Soul - Uninstall and cleanup?' OF COURSE!!! Click 'Yes, try uninstall'. 

5. After 5 minutes waiting it will fix the problem completely and enjoy the BnS!!!!  

PS: My system is windows 10 and i have no idea why the 'run now' is gray for me, so i went to Chinese microsoft websit find the same program and able to use. Here is the Chinese Microsoft websit link, just in case: https://support.microsoft.com/zh-cn/kb/290301   . Just scroll down a little bit and click '立即运行' and rest are same as 'General steps'. Hope this can help XD.

PS: Thanks for this guy's post on Korean website even though i don't know where is his/her name.  he/she gives me a clue of solution! http://bns.plaync.com/board/free/article/3153927 

[Kurotsuno]

Worked for me, thanks a lot.

[Naleesh]

YEAH! It worked! Finally! After month of trying and incompetent B&S support. Thanks!

[Angelius]

dude worked for me jesus i just wanted to go back in the game thank you so much :D