You are going to experience some trouble when you do surprise removals for the following: Removable storage devices which is letter B; Parallel and COM port devices which is letter C; and finally, applications which are letter D. There are a lot of people who have learned the hard way that suddenly removing removable storage devices can lead to the loss of data.
Some information cannot be retrieved anymore and will be lost forever. When the COM port devices are suddenly removed while they are still being used, expect that the whole system will hang and crash. Applications may suddenly stop working because of the removal of the needed device.
Removable storage devices. Parallel and COM port devices Applications
Data can be lost on removable storage devices if they are removed without first dismounting them. Removal of a parallel or serial device while their ports are being written to can cause the system to hang. Applications can also hang as the result of a surprise device removal.