sansa e250 problem with start up


I had not been using my sansa e250 for long. Now when I started it it powered on, and worked well. But now,after about three days,  it does not power on. When I press the power button or connect it with computer, Blue circle comes up, but screen remains blank. It is not recognised by the computer. Infact computer does not give any message at all. Please help.’

Thanks in advance. 

It could either be this or this.