It's not like .7z is an obscure format. I've been using it for nearly a decade now. Magazines like PC World has 7-zip in their best freeware lists year after year. Both WinRAR and WinZip supports this format.

http://www.7-zip.org/download.html

Your reason for not using it just seems silly to me.

it boils down to this, If I find I need 7zip compressed program to do something that is vital to me or the job I do then I will purchase the program. at the moment boinc is not a mission critical program nor are the addons for it. would I like to use the lastest optimize app, sure but it isnt a requirement to crunch. I asked once if someone would be willing to convert the file I needed which was for using my onboard intel graphics to crunch, i didnt get any offers and I as fine with that. when someone asked why I didnt just download and install 7zip I explained why I didnt want to. To me at the moment the program is not needed.

Perhaps you would like to ask a moderator to lock the thread,
since it seems to be devolving into a repeat of your previous thread.

Just an example as to why 7zip is great: its compression over zip.
I have a (transitioner-log) text file that's 18,991KB big. Using the 7zip archiver, I compressed it twice.
Using ZIP format, compression Ultra, compression method deflate, dictionary size 32KB, wordsize 256, this file compresses to 354KB.
Using 7zip format, compression Ultra, compression method LZMA, dictionary size 32KB, wordsize 256, this file compresses to 193KB.

We know why we use compression archivers, it's to make these files smaller on disk, but also smaller to download. I'm sure some of us don't mind if a file is 19 Megabytes or 193KB, since we have unlimited download capacity over a big download pipe. But not everyone has that, so when every byte counts towards your cut-off at the end of the month, the better compression is what counts.

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