Dual Boot, Win10 System Protection & Veritas 18 VSS Space Issues

20190712

Hi Folks!

I have a real conundrum here. Here's the system setup & thanks for your help in advance!:

Dual Boot SSD's, one has Win7Utl 64, the other Win10Pro 64. I mainly am still using Win7 as I migrate to Win10
Both 64bit fresh installs of latest builds as of this date.
BIOS is setup to only include Win7 drive in bootup drive list on an ASUS MB
At bootup in order to boot from the Win10 SSD I have to hit F8 to select the Win10 drive to boot from.
Both boot and function fine in this manner and remain segregated without access to one another through hidden drives.

On each boot drive, Win.x setup in Disk Mngt. I've removed the other's drive letters making them invisible to each other to avoid potential issues. So on Win7 the Win10 C: and it's System Reserved drive letters were removed and vise-versa. When booting to Win10, Win7 C: and it's System Reserved drive letters were removed. Works well because nothing can access the others drives from either OS.

The issue is Backing up with Veritas 18 sft. on Win7 side because of something weird going with System Protection settings on Win10. Win7 VSS error "Insufficient storage to complete shadow copy" when attempting to backup Win10 hidden drives from within Win7 boot environment. I do all my backuping from within Win7 and have for years using Ghost 15 without (much) issue.

I set both Win10 & Win7 SP setting the same, Enabled for boot drive (C:) only and a size of roughly 10GB. Oddly, Win7 SP is unaffected after a boot to Win10, but after rebooting back to Win7 and then back to Win10 again, Win10's SP settings are always changed to Enable for C:, but set to zero in size. What??? Why?

So I ran VSSadmin on both OS's to compare notes and see what the settings were from within Win7 and 10 which matched and they both had plenty of space (I think Win7 needs 32mb and Win10 370MB roughly for VSS).

So, I defined the same backups on the Win10 drive, ran the backups and both backups ran fine and mind you, I did not reset Win10's SP prior which was hosed up as usual and reset to Enabled and zero size on Drive C:.

So, I'm totally stumped on this... Why, from Win7's boot environment, VRS18 errors with VSS insufficient space error on Win10 's drives backup job, but from Win10 boot environment VRS18 runs both backups jobs fine irregardless of Win10 SP settings? In Win7 boot environment Ghost 15 (Veritas sft. licensed to Symantec) had no issues with running Win10's hidden drives backup jobs like clockwork?

What am I missing folks? I hope someone else has a similar setup that works with VRS18 who can shed some light on this...

I am still running dual boot because of older drivers that Win10 doesn't like for some of my hardware, so I still need both OS's as I try to find solutions for developers unable or incapable of supporting Win10 migration & support of their hardware & software incase you were wondering.

TIA! Prey

Just an update. After much research I found that there are free space requirements for VSS that differ between x32 and x64 Win OS's. x64 systems require at least 320mb of free space on the System Reserved partition in Win7 and the Recovery partition in Win10. The problem appears to be a Veritas specific issue. Many of us still use Veritas products (Ghost15.x & VSR18).

Backup the system with the almost full effected system partitions, get into the Win install advanced setup and delete the OS partition leaving only the System Reserved in Win7 or Recovery in Win10 x64 OS's. Now while still in Windows Advanced Installation "Extend " the 1st partition to equal 1GB and restore the remaining images from the backup manually. The system should reboot and function normally and you should not get the VSS Snapshot errors any longer. This has worked for me on both BIOS based systems and UEFI Bios based systems. Obviously the BIOS based systems are much easier since there is only 2 partitions, the boot partition and the OS partition. UEFI is a little bit tricker and you generally lose about 527MB of drive space because the system has to be reinstalled in the partition created beyond the 1st original partition, but deleting it and restoring the remainder will use the 1st newly extended partition because the partitions flags do not change. It retains it's Boot status. I've done 3 systems successfully this way and the small loss is well worth the capability and lost of headache gains.