iMac file system I/O error is one of the most catastrophic issue for any iMac users. It is a critical issue caused to corruption in file system. There are several reasons which can cause corruption in iMac file system such as abrupt system shutdown, catalog corruption, virus infection, hard drive crash, bad sector on hard drive, etc. Well, no matter what the reason but once this very error appears on iMac system, it is able to causes serious consequences including severe data inaccessibility issue. However, you can resolve iMac file system I/O error quite easily by using disk utility or FSCK command. Well, these manual methods are used to fix common issues on iMac and may fails in case of severe corruption problem. In such critical scenario you will no other option but o format your entire hard drive. It will surely causes severe data inaccessibility but there is no other option to fix iMac file system I/O error. Well, once the issues is complete resolves then you can easily get back all your lost or inaccessible data easily by using Mac Data Recovery Software. It is very effective advanced and easy to use tool. It allows easy recovery of all lost files in a very safe and hassle free manner. Hence, it is recommended to recover all formatted iMac files by using Mac Data Recovery Software after iMac file system I/O error.