System or Program component monitoring is now a "must" to avoid such dll injections. Most software firewalls has this useful feature which will monitor and alert users before a component (e.g. dll will be changed) to avoid injections.

There are also many free programs that help users to protect the system files from injections. One of them is called System Safety Monitor that can prevent so called "DLL Injection". Also, SSM will notify the user whenever a program you want to start was modified.

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