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After Windows 10 Anniversary update the grub OS choice menu no longer shows, I just get the grub prompt. From the grub prompt I can use ls on only one of the partitions, which has three folders: ubuntu, boot and windows but I'm not sure what to do from the grub command line.
I've tried using the boot-repair tool but it didn't work.
I tried the bcdedit approach mentioned here Windows 10 upgrade kills grub and boot-repair doesn't help but it didn't change anything.
I fear for the worst because the partition that had ubuntu on it is not recognized properly by gParted (it says file system unknown), and
fdisk -l /dev/sda6 says "Disk /dev/sda6 doesn't contain a valid partition table" I've not much experience with partitioning or grub, and maybe it's a wrong assumption, but since I have only two partitions with more than 100GB, and gParted says sda4 has the Windows label I've assumed that sda6 is my old Ubuntu partition.
I tried the accepted answer from here: How can I repair grub? (How to get Ubuntu back after installing Windows?) but immediately hit problems because I couldn't mount my ubuntu partition. Without type (or with
-t auto) mount says I must specify type, but with type I get:
sudo mount -t ext4 /dev/sda6 /mnt mount: wrong fs type, bad option, bad superblock on /dev/sda6, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so
Here is the output from
sudo parted -l
Model: ATA Crucial_CT250MX2 (scsi) Disk /dev/sda: 250GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Number Start End Size File system Name Flags 1 1049kB 735MB 734MB ntfs Basic data partition hidden, diag 2 735MB 1008MB 273MB fat32 EFI system partition boot 3 1008MB 1142MB 134MB Microsoft reserved partition msftres 4 1142MB 103GB 102GB ntfs Basic data partition msftdata 5 103GB 104GB 855MB ntfs hidden, diag 6 104GB 230GB 125GB 7 230GB 238GB 8468MB linux-swap(v1) 8 239GB 250GB 11.5GB ntfs Basic data partition hidden, diag
Here is the output from the recovery tool: http://paste.ubuntu.com/23276891/
I haven't tried TestDisk yet because I'm not sure if it can fix it (and I don't want to break the windows partition) but if anyone thinks it's worth trying I can do that.
Overall it's been a very sad anniversary for Windows for me. When I saw the Windows "Hi.. We've updated your PC" on screen I wanted to put my fist through it.
Update: I tried TestDisk and now windows isn't booting either after just doing the basic "scan" and write partition table.