Hardware Failure
Could you post a new question with more detail? Please describe what you mean by "double error". Thanks!
You will usually get an error during POST if there is a problem with a serial port.
It depends on what you mean by "deformed". If it's bent or damaged it has no value. If the coin's appearance is the result of a minting error (e.g. part of the design is missing) it could be valuable to a collector of error coins. Please post a new question with more details.
post -converter oxygen senser heater or circuit fault
easy
It places an error message in the BIOS.
There are several types of errors you can receive during POST if the hard drive is physically damaged. It could be anything from a simple "Bad Sector Read Error" to the dreaded "Bad Controller Error". Sometimes the BIOS won't receive the error though, especially is it's a bad sector which lies past the MBR (Master Boot Record) The only way to determine this is do an entire sector scan within Windows and then try to fix the sector. Major priority here is to do a backup immediately if you think the hard drive is going on you.
POST will indicate error messages by a series of beeps or a series of lighted-up LEDs (depending on your computer).
POST stands for power on self test it does basic hardware checks on the computer
A typographical error for "post meridiem" meaning afternoon.
Error message on monitor
One or more memory modules may be faulty or imporperly seated