Unlimited FREE upgrades to newer versions of OSS for 2 years.

两年无限制免费升级到新版本。

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In the hope that you voluntarily, to be registered as a formal version of the user, the registration of a long-term use of free upgrades and free!

希望在你自愿的情况，注册成为正式版用户，一次注册可长期免费使用和免费升级！

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In addition, this model can be further supplemented with advertising if the ratio of free users to upgrades is less than expected.

另外，如果免费用户中升级的比例低于预期，还可以通过广告进一步补充这个模型。

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What they get in return is unsurpassed access to priority check-in lanes, first-class lounges and free upgrades.

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But many salons offer free upgrades and add-ons, as well as hefty discounts.

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This workaround relies on the fact that Microsoft is currently offering, for a time limited period, free upgrades for the Media Center add-on, and it is this process that is flawed because Microsoft does not check the validity of the original key used to activate the copy of Windows 8 Pro before dishing out another key.

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