Technology a little bit abandoned, and today catching up a very comprehensive article, the original here, thanks author!!
Windows7 let us look at the common sense of the boot process:
computer power, the first is to start the BIOS, BIOS self-test is complete, find the hard disk's master boot record MBR, MBR read DPT (partition table) to find out the active primary partition, and then read the active primary partition of the PBR (partition boot record, also called dbr, exactly what the name on the network argument is not off, we may be called pbr it), PBR and then search for the boot manager partition file BOOTMGR, in BOOTMGR is found windows 7 activation key, control over the BOOTMGR.BOOTMGR read on boot bcd file (BCD = Boot Configuration Data, which is operating system latency is not zero, then it will appear on the display of the operating system selection screen. WINDOWS7 we choose to start after, BOOTMGR will go to the boot disk look WINDOWS system32 winload.exe, then winload. exe loaded windows7 kernel, which started the whole windows7 system.
this process can be simply summarized as: BIOS -> MBR -> DPT -> pbr -> Bootmgr -> bcd -> Winload.exe--> kernel to load -> the windows7 system
this paper to talk about the MBR -> DPT -> pbr -> Bootmgr -> bcd this section solutions to any problems that may arise.


mbr problems, mainly mbr code was rewritten, because the code was rewritten in different, so the error message vary. For example, we installed windows7 dual system with ubuntu, ubuntu changed the mbr, where we put ubuntu partition is formatted, can not enter both windows7, can get into ubuntu, boot time will be shown the error message:


[Figure I]
solution is to rewrite the mbr. to rewrite mbr, we know that in dos with fdisk / mbr command to rewrite. fdisk / mbr the rewrite mbr and xp are compatible, however, is not so compatible with a windows7. practice showed that: fdisk / mbr command to rewrite the mbr windows7, the need to rebuild bcd, or does not start windows7. a user pointed out, there is reason fdisk / mbr command to rewrite the mbr of the hard disk signature in general are to rewrite the mbr partition tool, such as diskgenius, rewrite the mbr it is compatible with windows7 can also be used bootrec / fixmbr command to rewrite To run Bootrec . exe tool, you must start Windows RE. To do this, follow these steps:
windows 7 installation CD inserted, start the computer from the CD-ROM, CD-ROM boot is complete, press shift + f10 key to bring up the cmd command prompt characters in the cmd command prompt, type: bootrec / fixmbr
Enter. This will rewrite the mbr.


[Figure II]

partition table problems for this problem, space is limited, do not do detail.
system tray is not active primary partition, as long as this situation with partition tools (such as diskgenius) the system disk can be set to active primary partition. pbr problems, mainly pbr code was rewritten, because they are rewriting the code are different, so is not the same error message, such as WINDOWS7 system, active partition, but was written for XP, pbr, this boot will be shown when prompted: [Figure III] simple solution is to use bootrec / fixboot command to rewrite the pbr: windows7 installation CD inserted, boot from the CD in the CD boot is complete, press shift + f10 key and call cmd command prompt in the command prompt, type: bootrec / fixboot Enter. This will rebuild the active partition of pbr. there is also a commonly used commands have to mention, this is the bootsect: windows7 installation CD inserted, boot from the CD in the CD boot is complete, press shift + f10 key and call cmd command prompt in the cmd command prompt, type: bootsect / nt60 sys / mbr Enter. This command overwrites the active partition of pbr, and will also rewrite the mbr, mbr and pbr for making windows7 and vista. bootsect.exe windows7 installation program is located in the boot CD-ROM directory, you can extract this file, under the command line in xp can run this program, you can also winpe command line to run under this program, so this program when it is convenient to use while bootrec.exe command not so convenient to use, so BOOTSECT command is applied more widely some of the. There is another point should be noted, vista installation CD inside the boot folder, there are with this gadget, but there is no vista of bootsect command / mbr parameter, so it can rewrite the pbr, but not rewrite the mbr, it is necessary to note. practice shows that: a hard disk mbr to clear, then run the bootsect windows7 command, can indeed be found mbr back to normal, which also shows the bootsect windows7 command can indeed rewrite the mbr. addition, bootsect command can also rewrite the xp mbr and pbr, but this is bootrec command does not to. xp recovery console with fixmbr command rewrite the mbr, using the fixboot command rewritten pbr. boot file if the problem is, commands can generally be re-written with bcdboot Boot file: windows7 installation CD inserted, boot from the CD in the CD boot is complete, press shift + f10 key to bring up the cmd command prompt in the command prompt, type: bcdboot x: windows / sx: note that this is the previous x: is the windows folder where windows7 disk, usually c:, c drive if you are not, please change the drive letter corresponding to this latter x: is the activity primary partition drive letter where the general is the c drive, so this command is written in general: bcdboot c: windows / sc: but need to note that in windows re environment, see the letter and You can see in the letter under windows7 might not be so need to use dir / a command to confirm the disk is correct. example: cd / dc: dir / a two command's role is, first enter the c: drive's root directory, then displays the c root directory of all files and folders, according to the displayed file or folder buy office 2010 key, you can determine the specific dish you look under the windows7 to which a disk. windows7 guidance document was bootmgr and boot folder inside the file, and boot files folder inside the main bcd file. bcdboot command specifies the sub-region in the re-write all the windows7 boot file. bcd file if it is only a problem, you can use bootrec command to rebuild the bcd: windows7 installation CD inserted, boot from the CD in the CD boot is complete, press shift + f10 key, tune the cmd command prompt in the command prompt, type: bootrec / RebuildBcd this command if found to not write bcd's windows7 or vista operating system, you will be prompted to write, prompted, enter Y also be written to. or use the bcdedit command to manually rewrite the bcd, but the operation is much more complicated. specific case studies: Case one: strange, not the system tray active primary partition in line to see a help, windows7 system is operating normally, but in disk management see is: The system tray is not active primary partition. [Figure IV] we have installed a version installed after the Restore Wizard button in the boot when pressing the F11 key to start a key to restore the program, but we format the system after-hours, in boot time is still can be operated while the so-called pbr is generated when high-level formatting, which shows that one key to restore the startup wizard code is not written into the active partition of pbr (if so, in the format time has been cleared), but write the MBR. through the first set in the MBR, Restore Wizard to read a key to the hidden partition, then read the activities of the primary partition. Well, now we have encountered this kind of situation is not also passed rewrite mbr and point to a specific partition? assume mbr no problem, then the problem may be in the pbr (also known as dbr), win7 the pbr code should be written in find bootmgr, but if this code is also provided to find a special file, and then go through this file to another partition in the boot bootmgr, so that we can not achieve the other primary partition becomes active The purpose of the system disk. the above analysis, we can get the conclusion: the problem is not in the mbr, that is the pbr, the solution is to first try to rebuild mbr, if not resolved, it can certainly problem lies in the pbr, pbr can solve the problem as long as the reconstruction of. so first of all re-mbr, the problem persists, then rebuild pbr, the problem really be solved. Case II: boot time appear: BOOTMGR is missing press ctrl + alt + del to restart. translated into is: bootmgr is missing, press Ctrl + Alt + Del to restart This is very common fault. Since it is bootmgr is missing, we generally just use bcdboot command to rebuild the boot file to. the causes of this situation, the general may have: bootmgr file does not, and this is the most common. One is caused by a disk error, this case, running under winpe look at chkdsk / f command may also be addressed. A friend of MFT fragmentation with Diskeeper sort, boot time, there have been this tip is estimated may be used DISKEEPER After finishing the disk for the MFT, which is the diskeeper or a bug, and therefore not recommended for use diskeeper mft defragmentation. a users curiosity. set up the C drive becomes active (active partition). This activity is set: right click on Computer - Manage - Disk Management Right-point C drive, set as active. by. how is it ah. actually does not start after reboot discount windows 7 key! display bootmgr is missing, Ctrl + Alt + Delete to restart. and then, or so. This is from the Internet to find a case, analysis can be concluded that he should be loaded in windows7 there is a hidden Reserved Partition is the real active primary partition, and he should be the c drive is not active. He put the c drive is set active, which means to cancel the so the error is inevitable. The solution is actually simply set active partition then the system can be retained. friend created problems, but did not seem able to finally solve the problem. so will those who really difficult, difficult person will not. Case III: a time of boot: BOOTMGR is compressed Press Ctrl + Alt + Del to restart
translated into is: bootmgr is compressed, press Ctrl + Alt + Del to restart the causes of this situation is that the system disk compression. The strange thing is, for this situation , we use bcdboot command to rebuild the boot file is not the solution. However, we can run the commands: compact / u / a / f / i / sc: * This makes the problem is resolved. compact program at windows system32 folder, so we must first use the CD command to enter the windows system32 folder where the assumption that the c: drive is the drive where the bootmgr, if not, to be replaced by the corresponding letter. online with a friend When this command does not solve the problem, the reason is that this friend is running the command is: compact / u / a / f / i / sc: not behind this *, so by running the command did not materialize purpose from the command itself provides help explain point of view, this * seems to be unnecessary, but the actual operation indicate that this * is required. This command will compress the C drive files have been completely extracted, The so-called real trouble should end it. note, only run the commands: compact / u / a / f / ic: bootmgr not solve the problem. that someone found, run exe / fixmbr, Bootrec / fixboot The BPB table and did not subsequently modified, so the BPB table partition information recorded information is inconsistent with the actual partition. run Bootrec / fixboot command rewritten bpb, so that makes two changes to the agreement. practice showed that: bootsect command can achieve the solution to this problem. that someone posts, that is installed xp and vista dual system, start the vista system there BOOTMGR is compressed, so he canceled the system in the xp disk compressed state, but the users would not credible, because if ntldr is also compressed, then the xp start time will appear: ntldr is compressed Press Ctrl + Alt + Del to restart Unless the friend is only compressed bootmgr, and no compression ntldr office 2010 ultimate key, but this is generally not possible. This compression is generally compress the entire disc when generated, if the compressed file, then specify the general bootmgr and no one to compress ntldr The Practice has shown that under the windows7, even if designated for the entire system disk compression, generally can not be compressed bootmgr, and will be prompted to deny access, but there will still be in power when the error message: bootmgr is compressed Case Four: first installed windows7, after the installation of linux, the linux system after a problem, can not enter either linux, can get into windows7, and there's reason mbr and activities partition pbr be rewritten as long as the active partition and rebuild mbr pbr, it can enter the windows7 the easiest way is to use bootsect command to solve: bootsect / nt60 sys / mbr Case 5: first installed windows7, after the installation of xp, there is no startup items windows7: This requires three steps to solve the problem: one, with the bcdboot command to rebuild the boot file windows7. two, with bootsect command to restore the mbr and pbr windows7 three windows7 after entering with the bcdedit command to add the xp startup items.Related Articles:
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