Windows Phone 7.8 is the most recent update for its smartphone OS, Windows Phone 7 and 7.5 Mango. It will give users the same new start screen as WP 8, re-sizable live tiles, new theme colors and a lock screen, and is the alternative to WP 8 for devices with a single-core processor.
Microsoft began rolling out this update to older phones, notably Nokia Lumia handsets, at the end of January, though many have not yet received it. One option is to force the process by downloading and running this program from WindowsPhoneHacker.com.
Your other option is to "cut ahead" in the update line by checking Microsoft's servers for your phone and grabbing the update manually, which is a fairly hit-or-miss method and only works for phones that are officially slated to receive WP7.8 anyway. The perk to this is that you'll get an official upgrade, which will be tailored to your device, rather than just WP7.8, which only includes the base functionality.
The process, courtesy of WPCentral, takes some patience, good timing and also requires the ability to disconnect your computer from the Internet.
Step-by-step guide
1. First, have the Wi-Fi and data on your phone turned off, then connect to Zune.
2. Navigate to Phone > Settings > Update, and the software should tell you whether or not an update is available. If it does, you can run the wizard and skip this guide altogether; if not, go to step 3.
3. Click another button (any option above or below "Update"), then hit the "Update" button again. Disconnect your computer from the Internet after one or two seconds by turning off its Wi-Fi or disconnecting an ethernet cable before it has a chance to tell you that your phone is already up to date. If it does, you'll need to try again.
4. After about 30 seconds, Zune should display a notification that an update is available, at which point you can reconnect to the Internet and continue with the update. The OS should be version 8858 — anything earlier, and you may want to repeat the steps above.
5. Install the firmware update at the very end. The process could take up to an hour.
WPCentral also reports that if this trick doesn't work, you can check again in a few days because the update may not be on Microsoft servers for your carrier/device yet, or it was never slated for a release anyway. In that case, if you still want 7.8, you'll have to use the tool or a manual CAB method (but do so at your own risk).
