Page Comparison

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1. Attempt to replace a file, providing the wrong checksum for the old file.
   1. The file shouldn't be replaced, and the user should be informed that the operation failed due to the invalid checksum for the old file.

Bad new file checksum

1. Attempt to replace a file, providing a bad checksum for the new file.
   1. The file shouldn't be replaced, and the user should be informed that the operation failed due to the invalid checksum for the new file.

Missing file replace

1. Attempt to replace a file that does not exist in the collection.
   1. The user should be informed that the operation failed because the file did't exist.

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