When you try to checkout documents, delete items or setup an alert on the library that is located on another site collection, you will get an error.

Here is the step to reproduce the problem:
You must have 2 site collections to test this. For example:
Site Collection 1: http://abc.support.com/sites/Team1
Site Collection 2: http://abc.support.com/sites/Team2

Make sure Site Collection 1 contains a document library. Let’s call it Shared Documents.

Steps:
1. Drop a list view into a page in Site Collection 2.
2. Point it to the Shared Documents in Site Collection 1 (use absolute URL: http://abc.support.com/sites/Team1 for the SiteURL attribute).
3. Display the Name and Title fields.
4. Save the properties.
5. Click on the down arrow in column 2 and select “Checkout”. You’ll get an error about invalid security validation (the correct behavior should be the document should be checked out).
6. Click on the down arrow in column 2 and select “Delete”. You will get an error message (the correct behavior should be the document should be deleted).
7. Click on the down arrow in column 2 and select “Alert Me”.
8. Setup an alert and click “Save”. You will get an error (the correct behavior should be the alert should save without any error).