yo, i just downloaded some software, and it was in .sis extention
it dis not work when i put it on my phone
so i changed it to .jar but that did not work neather
in wich extention do i have to change it?
or what do i have to do to make it work?

u dont have to, and you cant, change the format.
.sis files are completely different than .jar files, and will work only on symbian phones.
if they dont work on ur mobile phone, then sorry, u can use only .jar files. renaming wont work

sis files are for symbian phones, if your phone isn't a symbian it won't work.
Refer to your user guide for more info.

ok, thanks!

no "Read the faqs,use the search" sentence

hehehe was wondering the same thing...