Because Windows 7 (Vista is the same) is activated by touching the Slic information of your OEM through grub, so the Master Boot partition MBR is occupied by this grub to activate Windows 7.
However, if you want to install Linux in other partitions at the same time, a problem occurs: grub cannot be added to MBR; otherwise, Windows 7 activation will be damaged.
There are some complicated methods on the Internet, but a lot of command lines need to be entered. Here, we provide the simplest method without the need for command line.
In addition, you can easily repair Windows 7 or linux.
1. Install Win7 to drive C and activate it.
2. Normally install Linux to other partitions. When writing to grub is required, select the partition with the Linux Mount point! This step is very important because grub does not overwrite the grub of MBR in the partition where linux is located!
3. At this time, Win7 can be started normally, but there is no option to choose to enter linux. Download the easybcd software. The latest version is 1.72. It should be better and better.
[4. Open easybcd, select linux in add/remove entry, select grub for Type, add the Name you want in Name, and write a file such as archlinux, driver: select the partition where linux is located. The selected partition must be the same as the location where grub was installed when linux was just installed. The Partition Number Partition X may be different from that used in linux installation. The hard disk size is used to determine the Partition Number. After saving the add entry, you can see two options in view settings. One is originally win7 and the other is just created.
5. Restart and complete.
Finally, let's talk about the boot sequence. The computer starts and reads the grub of MBR (including grub of win7 activation information). Then run the bootmgr command of win7 to display the boot guide menu of win7, in this case, you can select the archlinux boot item to be added to go To the grub of the linux partition (this is another grub that is irrelevant to the MBR) and use this grub to guide linux, in addition, this grub can be directly modified in linux.
The core idea is to install grub of linux into a non-mbr partition, and then connect to grub of linux Through bootmgr of win7.
After Windows 7 is reinstalled, you can use easybcd again to repair grub in linux.
After linux is reinstalled, install grub to the linux partition. You do not need to change it in Win7.