The errors are given in descending order – the top most error is typically the application error. The errors beneath it go into more and more technical/explicit detail of what went wrong, usually down to the operating system level.

Thus the cause of the (application) exception at the top of the error stack is the (system) exception at the bottom of the stack. If we only look at the top and bottom errors, then:

ORA-00204: error in reading (block 3, # blocks 8) of control file

Oracle error, saying that it failed attempting to read a file. Why? The bottom error says:

O/S-Error: (OS 23) Data error (cyclic redundancy check).

O/S error obviously means that this is from the operating system. It tried to perform the file I/O requested by Oracle (application layer) and it failed. It reports a CRC data error on the file.

So is this an Oracle problem? No, the root error is from the o/s and it reports a CRC error on a file.

So should you have even asked for assistance here? Or should your first stop not have been going on google (or bling/yahoo/whatever) and searching “+windows+” (the o/s in question) and “+cyclic redundancy check+” (the error reported by the o/s)? Perhaps even throw “+ntfs+” into the search too (assuming that this is the file system being used).

One of the most important skills for a software engineer is the ability to solve problems – not technical details (like what is a CRC error?). The technical stuff you can look up in the reference docs and material. But if you do not try to understand a simple error stack and analyse the problem, you will never acquire the skill to solve problems. And always be reliant on the skills of others to spoonfeed you and tell you what the problem is.