Cydia error: running sub-process /usr/bin/dpkg returned an error code (2)

In certain cases when you installing apps on Cydia you might get following error:

Error: running sub-process /usr/bin/dpkg returned an error code (2)

This error message appears to be related to some file corruption in your Cydia.
To fix it, follow these steps:

1. Navigate to /var/lib/dpkg/ directory.
2. Rename "available" to "available-bak".
3. Rename "status" to "status-bak".
4. Rename "available-old" to "available".
5. Rename "status-old" to "status".
6. Start Cydia and allow it to load everything it needs. Try to install or remove some apps to verify the error is fixed.

Remove Cydia apps update notification

Sometimes, you'll notice update notification of jailbreak apps in Cydia. If you doesn't want to update certain apps for any reason and would like to remove the notification, follow these steps:

1. Using iFile, navigate to /private/var/lib/dpkg/
2. Make a backup of file "status"
3. Open the file "status" using iFile Text Viewer
4. Find the package that Cydia is asking you to update.
5. Change the version number to the new version number of to a higher number (hit the Edit button in the iFile Text Viewer).
6. Save the changes and restart Cydia then you can see the notification is removed.

If you would like to receive update notification of certain apps again, just restore the version number changed in step 5.