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Common Security Problems
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| The virtual memory storage of the Windows operating system is called the paging file (or the swap file). The operating system may store any information from the memory to the disk whenever it wants. This means that the paging file may contain passwords, pieces of documents and other sensitive information.
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| Since the operating system locks the paging file while it is running, the file cannot be accessed using standard file operations. There are applications that claim to overwrite the paging file by allocating huge amounts of memory, but this method may freeze your computer and even then the space allocated by applications cannot be accessed and not all the available space on the paging file is necessarily overwritten.
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| For information on how to erase the paging file, see Erasing Paging (Swap) File.
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| Unless you name your files with arbitrary names, the name of a file can reveal information about the file contents. Eraser will overwrite the filename when erasing the rest of the file.
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| Names of the files you have previously deleted may also still be stored in the file system table; Eraser will overwrite them when you erase unused disk space.
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| An executable file cannot be accessed when it is running, the same goes for shared dynamic link libraries and all files that are opened without file sharing allowed. The cluster tip area of these files may contain sensitive data the same way as the unused area in any other file, but it cannot be overwritten because the file is locked.
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| To reduce the amount of these locked files into a minimum, you should close as many applications as possible before erasing the unused disk space. Closing the applications will also free memory allowing the operating system to reduce the size of the paging file making more free space available for overwriting.
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| The files loaded in memory by the operating system, such as the system libraries, cannot be accessed at all while the computer is running. The cluster tip area of these files may contain sensitive information, but it is not very probable because these files are locked all the time.
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| When an area on the disk gets damaged for some reason, the disk electronics mark this area to contain only bad sectors. These bad sectors cannot be accessed so the data still stored in them cannot be erased either. Peter Gutmann has discussed this subject further in chapter "Further Problems with Magnetic Media" of his paper "Secure Deletion of Data from Magnetic and Solid-State Memory".
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