因此，您需要更改 Windows 机器上的启动顺序(boot order)，以便可以从USB启动以运行离线病毒扫描程序(offline virus scanner)？或者您可能需要更改启动顺序(boot sequence)以便可以从Windows DVD启动来运行系统修复(system repair)？
无论更改启动顺序(boot sequence)的原因是什么，访问BIOS的过程可能因计算机而异。差异将取决于您的计算机上是否有旧版BIOS或较新的UEFI BIOS，或两者兼有。
除了如何访问它们之外，我不会详细介绍这两种BIOS之间的差异。(BIOS)进入计算机上的BIOS后，您就可以更改引导顺序(boot order)。
访问旧版和 UEFI BIOS
所以首先让我们谈谈进入BIOS。如果您不确定您的计算机是否使用Legacy 或 UEFI BIOS(Legacy or UEFI BIOS)或Legacy + UEFI，这实际上是第三种选择，那么您只需要进行一些试验和错误(trial and error)。
每个人都可能熟悉旧版BIOS ，因为这是您在计算机首次启动时通过按某个键（如DEL、F2、F8、F12或ESC ）访问的那个。(ESC)
首先要做的是继续并重新启动计算机，然后在计算机启动时不断按下键盘上的一个键。通常，您会在底部看到一条消息，告诉您要按哪些键。以下是戴尔机器(Dell machine)和我家的定制机器的两个示例：
我的定制 PC 上的主板来自MSI，因此启动过程会加载一个MSI 屏幕(MSI screen)，其中包含按DEL运行BIOS 设置(BIOS setup)或按F11运行启动菜单(boot menu)的选项。请注意，如果您进入BIOS 设置(BIOS setup)，您也可以从那里更改引导顺序(boot order)。由于更改引导顺序(boot order)是一项常见任务，因此它们通常有一个单独的键（在本例中为F11）。
在我的Dell上，我获得了一组不同的键来访问BIOS 设置( BIOS setup)(F2) 和引导选项( Boot Options)( F12 )。现在，如果您在启动时根本没有看到此类消息弹出(message popup)，则可能表明您的BIOS仅针对UEFI设置。
UEFI BIOS无法通过按键盘上的键来访问。相反，您必须以特殊方式重新启动Windows，然后通过一些菜单选项。要重新启动Windows，请单击开始(Start)，然后单击设置(Settings )（齿轮图标）。
接下来点击更新和安全(Update & Security)。
然后单击左侧菜单中的恢复，然后单击(Recovery)高级启动下的(Advanced startup)立即重新启动(Restart now)按钮。这将重新启动您的计算机并加载高级恢复选项屏幕。在这里，您要单击疑难解答(Troubleshoot)。
在疑难解答标题(Troubleshoot heading)下，继续并选择高级选项(Advanced Options)。
在最后一个屏幕上，您应该会看到一个名为UEFI Firmware Settings的选项。
如果您没有看到此选项，则表示您的计算机没有UEFI BIOS。相反，您必须通过在启动时按下键来使用传统方法(legacy method)启动。请注意，如果您的BIOS设置为UEFI + Legacy BIOS，那么您将能够访问这两个BIOS。
更改引导顺序
现在我们知道如何访问BIOS，让我们更改Windows中的启动顺序(boot order)。如果您的计算机使用的是旧版BIOS，请确保按下启动选项或启动顺序(boot order)键，因为这将使您直接进入启动顺序屏幕(boot sequence screen)。
例如，在我的戴尔机器上(Dell machine)，当我按F12选择Boot Options时，我得到以下屏幕：
在顶部，它告诉我我的引导模式(boot mode)设置为UEFI + Legacy，然后它给了我Legacy Options和UEFI Options。如果您的计算机上没有任何UEFI硬盘驱动器或设备，您只会看到Windows Boot Manager。现在我可以选择我想从哪个设备启动。
在我的自定义机器上(custom machine)，按F11进入启动菜单(boot menu)让我进入以下屏幕：
如前所述，您可以像这样直接进入引导选项，也可以进入设置然后进入引导部分(boot section)。有时通过设置会给你更多的选择。例如，在我的定制 PC 上，我输入了BIOS setup，然后是Settings，然后是Boot。
正如您从下面的列表中看到的那样，有很多选项。基本上，BIOS列出了所有UEFI 和传统引导选项。(UEFI and legacy boot options)因此，如果您有UEFI硬盘驱动器和旧硬盘驱动器，则可以选择所有设备的引导顺序(boot order)。
当您在BIOS 引导(BIOS boot) 顺序屏幕(order screen)中时，您将看到有关如何更改顺序的说明。有时您使用向上和向下箭头键，有时使用PgUp 和 PgDown 键(PgUp and PgDown keys)，其他时候您只需选择Boot Option #1，如上，然后选择首先启动的设备等。方法取决于主板制造商(motherboard manufacturer)，因此请遵循屏幕上的说明。
同样，如果您没有UEFI 固件设置(UEFI Firmware Settings)选项并且在启动期间看不到任何按此键设置(Press this key for setup)消息，那么只需尝试重新启动并在 PC 启动时按上述键之一几次向上。不要(Don)按住键，一直按它。如果一个键(key doesn)不能让您进入BIOS，请再次重新启动并按另一个键。如果您在进入BIOS或更改引导顺序(boot order)时遇到任何问题，请发表评论，我们会尽力提供帮助。享受！
Access BIOS & Change Boot Order for Any Version of Windows
So you need to chаnge the boot order on yoυr Windows mаchіne so that уou can boot from USB in ordеr to run an offline virus scanner? Or maуbe you need to change the boot sequence so that you can boot from a Windowѕ DVD to run a sуstem repair?
Whatever the reason for changing the boot sequence, the process of accessing the BIOS can vary by computer. The difference will depend on whether you have a legacy BIOS or the newer UEFI BIOS on your computer or both.
I won’t go into details on the differences between the two types of BIOS, other than how to access them. Once you have gotten into the BIOS on your computer, you’ll then be able to change the boot order.
Access Legacy & UEFI BIOS
So first let’s talk about getting into the BIOS. If you’re not sure if your computer is using Legacy or UEFI BIOS or Legacy + UEFI, which is a third option actually, then you just have to do some trial and error.
Everyone is probably familiar with the legacy BIOS because that’s the one you access by pressing a certain key like DEL, F2, F8, F12, or ESC when your computer first starts up.
The first thing to do is go ahead and restart your computer and then to keep pressing one of the keys on the keyboard continually while the computer is booting up. Usually, you will see a message quickly appear at the bottom telling you which keys to press. Here are two examples from a Dell machine and a custom built machine I have at home:
The motherboard on my custom PC is from MSI, so the boot up process loads a MSI screen with the option to press DEL to run BIOS setup or press F11 to run the boot menu. Note that if you go into the BIOS setup, you’ll also be able to change the boot order from there too. Since changing the boot order is such a common task, they usually have a separate key just for that (F11 in this case).
On my Dell, I get a different set of keys for accessing the BIOS setup (F2) and Boot Options (F12). Now if you don’t see this type of message popup at all when booting up, it could indicate that your BIOS is setup for UEFI only.
UEFI BIOS cannot be accessed by pressing keys on the keyboard. Instead, you have to restart Windows in a special way and then go through some menu options. To restart Windows, click on Start and then Settings (gear icon).
Next click on Update & Security.
Then click on Recovery in the left-hand menu and then click on the Restart now button under Advanced startup. This will restart your computer and load the advanced recovery options screen. Here you want to click on Troubleshoot.
Under the Troubleshoot heading, go ahead and choose Advanced Options.
On this last screen, you should see an option called UEFI Firmware Settings.
If you don’t see this option, that means your computer does not have an UEFI BIOS. You’ll instead have to boot using the legacy method by pressing the keys on startup. Note that if your BIOS is set to UEFI + Legacy BIOS, then you’ll be able to access both BIOS’s.
Change Boot Order
Now that we figured out how to access the BIOS, let’s change the boot order in Windows. If your computer is using legacy BIOS, make sure to press the key for boot options or boot order as that’ll get you right into the boot sequence screen.
For example, on my Dell machine, when I pressed F12 for Boot Options, I got the following screen:
At the top, it tells me my boot mode is set to UEFI + Legacy and then it gives me Legacy Options and UEFI Options. If you don’t have any UEFI hard drives or devices on your computer, you’ll just see Windows Boot Manager. Now I can just pick which device I want to boot from.
On my custom machine, pressing F11 for the boot menu gets me to the following screen:
As mentioned earlier, you can either go directly to the boot options like this or enter setup and then go to the boot section. Sometimes going through setup will give you more options. For example, on my custom PC, I entered BIOS setup, then Settings and then Boot.
As you can see from the list below, there are a whole lot of options. Basically, the BIOS has all the UEFI and legacy boot options listed. So if you have a UEFI hard drive along with a legacy hard drive, you can choose the boot order for all of the devices.
When you are in the BIOS boot order screen, you’ll see instructions for how to change the order. Sometimes you use the up and down arrow keys, sometimes the PgUp and PgDown keys, other times you just select Boot Option #1, like above, and pick which device boots first, etc. The method is dependent on the motherboard manufacturer, so follow the on-screen instructions.
Again, if you don’t have the UEFI Firmware Settings option and you don’t see any Press this key for setup message during startup, then just try restarting and pressing one of the keys mentioned above a couple of times while the PC is booting up. Don’t hold the key down, just keep pressing it. If one key doesn’t get you into the BIOS, then restart again and press a different key. If you have any trouble getting into the BIOS or changing the boot order, post a comment and we’ll try to help. Enjoy!
