将以下文本总结为3句话，并讲明白.apk结尾的程序是什么意思。

Microsoft has confirmed the malware proliferation on its store and is taking steps to combat the issue, having already purged close to 3,000 malicious apps. "Since the launch of the Windows Store, we have had a robust set of technical, policy and enforcement measures in place to protect customers from apps that violate our policies, and we've evolved these policies and technologies as the app landscape has matured, " said a Microsoft spokesperson. Despite these measures, the company acknowledges the potential for more to be done. Additionally, the spokesperson went on to provide tips for users to identify malware, emphasizing that files with the .apk extension are especially risky and should be treated with caution.
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微软确认其应用商店存在大量恶意软件，并已移除近3,000个恶意应用程序。微软发言人表示，自Windows商店推出以来，公司一直采取了一系列技术、政策和执行措施来保护用户，但仍存在改进空间。发言人还提醒用户，尤其需要注意以.apk结尾的文件，这些文件可能存在较高的风险，应谨慎处理。
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