Recently I have come across the following problem : when I download a *.sis or *.sisx file directly on my e61 it will not install anymore. Basically the file is recognized as a NotePad file and opened as such on the device. I do not recall I have made any changes to the settings of the phone, thus to me the only conclusion can be that this is a result of the firmware upgrade. For sure it worked properly in the past.
Would appreciate if anyone can comment whether they have the same problem, and if so, what the solution is for it.

Hi,
I have the same problem on my E61 but I am not sure if it is down to the firmware upgrade as it is only with certain files. When I tried downloading some themes onto my handset through my WiFi connection they loaded up with the Notepad application but hen I tried it through my 3G connection and it was fine.
Thanks for the great site.
HI.YOUR PROBLEM OF OPENING sis files in text is due to wrong headers given by download servers gives header as text/.txt.so your phone opens them in notes.solution for your problem is open your phones temp. Dir. with third party file explorer and copy the file to your nokia/install directory and install it from there.hope this helps.pratik
hi, all u do is go to the certifcates in settings and choose the settings for the symbiam certs, change the online setting to yes..and save..all done
I resorted to using Opera Mobile (not mini) to download these apps, works perfectly. Only a trial version, but since i’m setting up my new e61 for the first time, it’s making my life easier! Mark, your solution is for a different error i think…