Email support@modernwarfare4cheats.com. Include your order ID and a short note about the issue.
Check FAQ and Status before you write. Many setup questions are already covered.
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One address handles everything: support@modernwarfare4cheats.com. Pre-sales questions, delivery problems, setup trouble and hardware resets all land in the same queue and get the same treatment.
The single biggest speed factor is what you include. Order reference, Windows version, GPU, CPU and a screenshot of the error turn a two day email exchange into a two reply one. For setup issues, add at which step of the guide things stopped.
Response time is measured in hours, occasionally minutes, essentially never days. If a game patch has the toolkit down, check the status page first - if the status page is green and your end is not, that is exactly what the email queue is for.
Hardware resets get their own mention because they are the most common request: moving the license to a new motherboard or drive is a same-day request, not a negotiation. Include the order reference and a sentence about what changed in the machine.
Before writing in, the two fastest self-serves are the status page for anything build-related and the FAQ for anything purchase-related. Both are updated by the same people who answer the email queue, so they never disagree with each other.
One housekeeping note: keep the delivery email. It holds the order reference that every request starts with, and it is the fastest way for a future you to prove a past purchase when a hardware reset or renewal question comes up months later.