problem with installation of last version 9.08

I installed version 9.02 (ok ) than I try to upgrade and I get the following message...

Fatal error: Allowed memory size of 16777216 bytes exhausted (tried to allocate 1802172 bytes) in C:Inetpubvhostsjodoigne.orghttpdocsquartier-sudlibrariesjoomlafilesystemarchivezip.php on line 305

Found the solution in FAQ: just instal the upgrade from the tmp directory of joomla, But why does it work with older version and not with newer ????

demeester wrote:

I don't know.
During web-install joomla uploads the file, unpack it into temporary directory, and then uses install from directory. So, the only difference is that you save some time/memory in the case of direct install from directory.