Recovery Guides: step-by-step DiskPatch operations:
Changing partition attributes.

A list of terms used in this page and their explanation can be found here.

 
Problem PC does not boot but partitions are okay
Symptoms blank screen at boot time
Solution change partition attributes (set a partition as 'active')
 
Why do we need to do this?

If you have just rebuilt the partition tables there's a good chance that DiskPatch had to create a new MBR from scratch. DiskPatch does not set any bootable partition to 'active'. This is done so that you can not accidentally restart the pc and start from a partition that may still be damaged: Windows might be inclined to run 'chkdsk' and that could very much ruin your day.
So if you checked the results of the partition table repair and everything is okay, you may need to set a partition active and allow the pc to boot the operating system that it contains.
 
Things you need to know before we start:
  • In the world of disks and data recovery we start counting disks at 0 (zero). So the first disk is 'disk 0', the second disk is 'disk 1', etc.
  • Use the cursor keys to navigate the menus, use the <Enter> key to select an option, use the <Escape> key to abort or leave a menu.

Here we go:

Start DiskPatch and select the disk.


example: your screen will differ. Find more information on how to select a disk here.

After selecting the disk, the menu will expand, showing actions that can be performed for the selected disk.
The selected disk will be marked in high intensity blue in the disk list (disk 0 in our example).

Now select 'MBR related tasks', then 'Change partition attributes'.

The partitions that are present in the MBR are displayed, along with their status (active, hidden).
The partition in our example (a 1Gb FAT32 partition) does not have a status set.

Select the partition and press <Enter> to display the attribute menu.

Select the appropriate option and press <Enter>. In our example we'll set the partition active so the PC can boot from it.
Changes are saved immediately, there's no need to confirm anything when setting partition attributes.

The attribute is now set. Press <Escape> to exit the 'Change partition attribute' menu.
 
Please  note:
  • Only 1 partition should be set active; setting 2 or more active partitions will render the PC unbootable.
  • Only primary partitions should be set active. Hiding can be done for both primary partitions and the extended partition.

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