Asking for help on file system filter driver

Hello, all!

I’m writting a file system filter driver, But now I’m meeting a headache
Please help me with following problems:
The file system filter driver was used to encrypt/decrypt the data.
But when we use the Wordpad or MicrosoftOffice to save the file,
it does not encrypt the data correctly. For Office file this is happened
only when
the file size is over 10MB(it is dependent on the memory of the computer).
But the data were encrypted correctly by our filter driver when the
file size is less then 1MB ~ 2MB. For text file, if we use the notepad to
save the file, it don’t work correctly when the memory is smaller than
on WindowsXP. But if the memory of the computer is over512MB, it works
Could you please give me some advise on the problems.

Thank you in advance!

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