解决方法：1.用光盘或者U盘启动winpe，进入命令提示符。2.输入“cd windowssystem32”，按回车。3.输入“bcdedit”，按回车，显示如下：(如找不到bcdedit.exe或系统为64位)Windows Boot Manager--------------------identifier {bootmgr}device unknowndescription Windows Boot Managerlocale zh-CNinherit {globalsettings}default {default}resumeobject {0a15e9fb-e924-11de-847b-d1bec5c6a45b}displayorder {ntldr}{default}{7619dcc9-fafe-11d9-b411-000476eba25f}toolsdisplayorder {memdiag}timeout 30Windows Legacy OS Loader------------------------identifier {ntldr}device unknownpath
tldrdescription 早期版本的 WindowsWindows Boot Loader-------------------identifier {default}device unknownpath Windowssystem32winload.exedescription Windows 7locale zh-CNinherit {bootloadersettings}recoverysequence {0a15e9fd-e924-11de-847b-d1bec5c6a45b}recoveryenabled Yesosdevice unknownsystemroot Windowsresumeobject {0a15e9fb-e924-11de-847b-d1bec5c6a45b}nx OptIn4.请注意上面的“unknow”部分，我们需要bcdedit进行修改。我的系统XP装在C盘，Win7安装在E盘，请根据您系统的实际情况输入以下命令：bcdedit /set {bootmgr} device partition=C:bcdedit /set {ntldr} device partition=C:bcdedit /set {default} device partition=E:bcdedit /set {default} osdevice partition=E:重新启动电脑！