after build version update power button lock

[GRR1]

When I click on power n lock button, sometimes lock screen is not coming its showing blank screen, please help me out why it is happening?

[Uliwooly]

Repair your phone

Update Service (SUS)

PC Companion (PCC)

Bridge (for Mac)

Alternatives on How to backup Xperias

http://talk.sonymobile.com/thread/36355