Install XP and Ubuntu dual system problem--ubuntu The original system is not recognized during installation

My host originally installed Windows XP and unbuntu15.04, because under the Ubuntu accidentally uninstall a dependency, unable to log on to the desktop, the web looked up a lot of information, the reasons for various, the solution is also various, and ultimately has not solved the problem. Various updates, various patches, various commands are tried, and then the level is limited, tossing for 2 days, do not want to helpless under, can only choose to reload. Specific to solve the process of logging into the desktop I have not written in detail this time, too messy, too much, I have not remember how many methods used, are invalid, so the need for friends, or Baidu to see it, here is no longer caught dead.

The thought of reloading is a very brain-free and easy things, who know this encounter a little trouble, so the birth of this small bo.

Problems encountered:

After downloading and making the Ubuntu14.04 USB boot disk (about how to download and make Ubuntu USB installation disk Baidu Many, please find yourself), into the installation interface no longer, but can not find my original installed XP and Ubuntu system. I used the fdisk-l command and did not find any problem, and the Fdisk parameter is not familiar, and did not delve into the study, but the online someone may be prompted by the disk partition table is a problem, so I decided to enter the Windows system with Diskgenius software detection, Sure enough the test results show that the last Ubuntu/home (/DEV/SDA9) partition exceeds the hard disk edge, then how to solve, I tried to use the software comes with the repair tool repair, but it will automatically format the last partition into NTFS format, we all know that NTFS is the format of XP, and Ubuntu needs ext format, so this method does not work.

Then continue to search for the tools of the Ubuntu repair Disk, found 2 more reliable tools, one is TestDisk, and the other is my previous use of Fdisk (because I did not study the parameters before, later discovered that Fdisk is so powerful). I first use TestDisk, because the name is easy to understand, the feeling is also very professional, use it is also very professional, various options, but it is easy to understand, one page shows/dev/sda2,/dev/sda9 are belong to the extend partition, and SDA2 system type is Win95 Ext ' d (LBA), SDA9 's system type is Linux, the description sda2 contains SDA9, which is also shown, the most important is that the sda9 of the editing range has exceeded the maximum range of sda2, which can certainly be a hard disk partition problem, It may be that the hard disk is used too long and the space shrinks further. Then it suggested me to re-establish the partition table to allocate the hard disk, unfortunately it's repair process almost with Diskgenius, also will be the last Ubuntu partition directly into NTFS, so fallback.

Finally began to study Fdisk, the scene is coming, of course, to detail, but unfortunately no picture with:

1st,sudo fdisk-l, display hard disk partition table information, display 2 hard drives, respectively, SDA, SDB, natural we are concerned about our local disk SDA, and SDB is just a USB installation disk

2nd,sudo FDISK/DEV/SDA, at this time, the command line prompts you to select M to display all the parameter information, as done, enter M

3rd, after entering m, display a row of information, we can use the P command to display the partition table of course this hard disk, you will not find the problem.

4th, after showing the partition table, I try to use V to verify partition table, the result is sad and happy, sad because the show sda9 partition is not completely within the SDA2 partition, HI is because we further verify the problem.

5th, and then press M, found that there are 2 Add (n) and delete command (d), you try to manually adjust the partition table, first delete the swap partition, and then add a small swap partition. (Note that when deleting the partition, I was the/etc/fstab under the relevant partition configuration lines are commented, added after the recovery, this step is not necessary, not verified, the reader can try on their own). The result is not as intended, and the same error is reported when executing v again, indicating that the address of the/DEV/SDA9 (/home partition) has not changed or is out of bounds.

6th, try to delete the/home partition again (it needs to be re-installed anyway, it will be formatted), and then add the/home partition again, after this operation, the execution v command finally did not report the cross-border error, see the Dawn

Reboot, enter the USB boot mode, sure enough, Ubuntu installation system can identify the original XP system and ubuntu15.04 system.

The end of this article (the only regret, no evidence).

　　

　　

Install XP and Ubuntu dual system problem--ubuntu The original system is not recognized during installation