Share your experience!
Good day!
I plugged my xperia active into my computer today to find out that an update for 587 was available from the PC Companion. Excited, I started the update. The update process went smoothly all the way till the end (it downloaded, processed, etc.) and at the last moment, during the finalization process, the update window closed (by its self) and the PC Companion said that no update was available for my phone (I checked the phone, its still 431). Trying to make it work again, I opened my phone, removed the battery, waited, then put in the battery again and restarted the phone. Again connecting it to the PC showed me the available update. Unfortunately, the same thing happened again. At the end of the update process, I was informed that there was no update available for my device. Can someone please help me with this issue?
I had exactly the same problem, I hope we will get an answer soon.
same problem 
pc companion and Update_Service_Setup-2.12.11.22
hello. same problem ...
I tried 2 times but I always get the same error
me too.
Worked just fine for me.
This morning I did the procedure again and I was able to upgrade!!!
Now the phone is at version 4.1.B.0.587 
Please let me know if you guys get the same problem using SUS.
Thank you for your reply. I tried the update this morning and it updated successfully!
Edit: I updated using the PC Companion software
thank you, SUS worked for me too.