My older laptop is an HP Pavilion dv6700. For about the last year, I've been almost afraid to turn it off. Often, it won't restart without crossed fingers and many tries.

The most often response I see is "Operating System Not Found". At this point the motor is running full blast. I can press the OFF button and sometimes it comes back like nothing happened, and sometimes I go through a process of taking out the battery, letting it cool, and trying again.

It works fine when it's working! McAfee is installed and scans when it stays on long enough (this laptop is rarely used [maybe for 30 minutes every few days], but has never caught a bug). SpyBot hasn't caught anything in over a year.

Any ideas what might be wrong?