update problem

I have upgraded from Ubuntu 9.10 to 10.04 but in the time that ubuntu are upgrading I lost my internet connection so many packages didn't download or installed but the upgrade continue fine but after finishing I tried to update and after downloading packages at the time of installing updates problem show up

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Extracting templates from packages: 100%
Preconfiguring packages . . .
(Reading database . . . 95%dpkg: unrecoverable fatal error, aborting:
 failed in buffer_read(fd): files list for package 'linux-headers-2.6.32.21-generic' : Input/output error
E: Sub-process /user/bin/dpkg returned an error code (2)
A package failed to install. Trying to recover
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How can I fix this problem?