Is there a 4 TB subscription "For Server" and can I backup Hyper-V with it?

1. Evidently no, but you can use the 3-TB Virtual Machines subscription.
2. Yes.
More info about this stuff:
If your backups are likely to exceed the storage quota for this type of subscription, you may want to use a subscription with larger storage quota. For example, you can use a server subscription or a subscription for virtual machines on a workstation. Or, you can use a subscription for virtual machines on a server which is not a virtualization server.

The inverse usage is not possible. You cannot back up a server using a workstation subscription. If you try to back up ESX(i) or Hyper-V virtual machines from the host that uses a server subscription, the backup will fail. With a server subscription, you can only back up the Windows host. With a subscription for virtual machines, you can back up both the Windows host and its virtual machines.
http://www.acronis.com/support/documentation/ABROA/index.html#18281.html

More info about Hyper-V host backup:
http://www.acronis.com/support/documentation/ABR11.5/index.html#19851.h…

Would this explain why I am getting an error when backing up? I setup a trial for the "For Server" subscription but I am backing up a Windows Server that has virtual machines in it. If so, how can I change the trial to a "For Virtual Machines" subscription?

Here are the errors:

================
9/19/2013 4:25:41 AM
================
Operation with partition 'E:' was terminated.
Details:
Write error.

Error code: 0x70004
$module = "disk_bundle_vs"
Tag: 0x9D2DE1F088CBC4D8
Request result error.

Error code: 0x9800E1
$module = "disk_bundle_vs"
Tag: 0xFBCF2EEB5A0351FE
Additional info:
--------------------
Error code: 502
Module: 1
LineInfo: a164035b3ff39287
Fields: $module : disk_bundle_vs
Message: Operation with partition 'E:' was terminated.
Details:
Write error.

Error code: 0x70004
$module = "disk_bundle_vs"
Tag: 0x9D2DE1F088CBC4D8
Request result error.

Error code: 0x9800E1
$module = "disk_bundle_vs"
Tag: 0xFBCF2EEB5A0351FE
--------------------
Error code: 4
Module: 7
LineInfo: 9d2de1f088cbc4d8
Fields: $module : disk_bundle_vs
Message: Write error.
--------------------
Error code: 225
Module: 152
LineInfo: fbcf2eeb5a0351fe
Fields: $module : disk_bundle_vs
Message: Request result error.
--------------------

================
9/19/2013 4:25:41 AM
================
Command 'Backing up' has failed.
Additional info:
--------------------
Error code: 61
Module: 309
LineInfo: 4a8728dc8a1c94f4
Fields: $module : service_process_vs
Message: Command 'Backing up' has failed.
--------------------
Error code: 3
Module: 329
LineInfo: 1cd98aae889424f9
Fields: $module : disk_bundle_vs
Message: Backup has failed.
--------------------
Error code: 1060
Module: 1
LineInfo: b43e776571144dec
Fields: $module : disk_bundle_vs
Message: Failed to commit operations.
--------------------
Error code: 4
Module: 7
LineInfo: 9d2de1f088cbc4d8
Fields: $module : disk_bundle_vs
Message: Write error.
--------------------
Error code: 225
Module: 152
LineInfo: fbcf2eeb5a0351fe
Fields: $module : disk_bundle_vs
Message: Request result error.
--------------------

Error code: 225
Module: 152
The error code for it is ERROR_SOCKET_SEND. It means that most likely is not some kind of imposed restriction. Also error message indicates that you have build 17437 or 17440 installed. Is there a reason to not upgrade? Backup to online storage was significantly improved in later version (11.5)

The download link was provided to me when I signed up for the trial in the attached page. This was the link to the download: http://download.acronis.com/trial/ABR11S_trial_en-US.exe

When I go to the installed program under Help > Check for updates, it tells me there are no updates available. How can I upgrade?

Use download.acronis.com/trial/ABR11.5S_trial_en-US.exe

'Check for Updates', IIRC, checks only for the last build of the installed product version - i.e. if you have version 11, it doesn't prompt for new build of version 11.5 .

Thank you. I uninstalled the previous version. I downloaded and installed 11.5. But now when I run a backup, I get the following errors. Please advise:

Access to the file is denied.
Additional info:
--------------------
Error code: 20
Module: 4
LineInfo: d355f41e7bb8d137
Fields: $module : disk_bundle_vs_37687
Message: Access to the file is denied.
--------------------

Command 'Backing up' has failed.
Additional info:
--------------------
Error code: 61
Module: 309
LineInfo: 4a8728dc8a1c950f
Fields: $module : service_process_vs_37687
Message: Command 'Backing up' has failed.
--------------------
Error code: 3
Module: 329
LineInfo: 1cd98aae889424f9
Fields: $module : disk_bundle_vs_37687
Message: Backup has failed.
--------------------
Error code: 1060
Module: 1
LineInfo: 145a191bfe9050bf
Fields: $module : disk_bundle_vs_37687
Message: No operation for executing.
--------------------

I retried it again this afternoon and now it seems to be backing up.

Well after 1 day and 10 hours of 'backing up', it ended with a 'Failed' result with the following errors. This is going to be my final attempt of this trial and will be moving on to another vendor unless support can tell me why it is failing. Here is the log:

--------------------
Log Entry Details
--------------------
Type: Error
Date and time: 9/25/2013 1:28:25 AM
Backup plan: Backup 9/23/2013 2:27:29 PM
Task: Incremental backup
Code: 20,250,685(0x135003D)
Module: 309
Owner: Administrator@VM2
Message:
Command 'Backing up' has failed.
Additional info:
--------------------
Error code: 61
Module: 309
LineInfo: 4a8728dc8a1c950f
Fields: $module : service_process_vs_37687
Message: Command 'Backing up' has failed.
--------------------
Error code: 3
Module: 329
LineInfo: 1cd98aae889424f9
Fields: $module : disk_bundle_vs_37687
Message: Backup has failed.
--------------------
Error code: 1060
Module: 1
LineInfo: b43e776571144dec
Fields: $module : disk_bundle_vs_37687
Message: Failed to commit operations.
--------------------
Error code: 4
Module: 7
LineInfo: 9d2de1f088cbc4d8
Fields: $module : disk_bundle_vs_37687
Message: Write error.
--------------------
Error code: 225
Module: 152
LineInfo: fbcf2eeb5a035218
Fields: $module : disk_bundle_vs_37687
Message: Request has failed with error code 9961697.
--------------------
Acronis Knowledge Base: http://kb.acronis.com/errorcode/

Event code: 0x0135003D+0x01490003+0x00010424+0x00070004+0x009800E1

--------------------

--------------------
Log Entry Details
--------------------
Type: Error
Date and time: 9/25/2013 1:28:25 AM
Backup plan: Backup 9/23/2013 2:27:29 PM
Task: Incremental backup
Code: 66,038(0x101F6)
Module: 1
Owner: Administrator@VM2
Message:
Operation with partition '0-0' was terminated.
Details:
Write error.

Error code: 0x70004
$module = "disk_bundle_vs_37687"
Tag: 0x9D2DE1F088CBC4D8
Request has failed with error code 9961697.

Error code: 0x9800E1
$module = "disk_bundle_vs_37687"
Tag: 0xFBCF2EEB5A035218
Additional info:
--------------------
Error code: 502
Module: 1
LineInfo: a164035b3ff39289
Fields: $module : disk_bundle_vs_37687
Message: Operation with partition '0-0' was terminated.
Details:
Write error.

Error code: 0x70004
$module = "disk_bundle_vs_37687"
Tag: 0x9D2DE1F088CBC4D8
Request has failed with error code 9961697.

Error code: 0x9800E1
$module = "disk_bundle_vs_37687"
Tag: 0xFBCF2EEB5A035218
--------------------
Error code: 4
Module: 7
LineInfo: 9d2de1f088cbc4d8
Fields: $module : disk_bundle_vs_37687
Message: Write error.
--------------------
Error code: 225
Module: 152
LineInfo: fbcf2eeb5a035218
Fields: $module : disk_bundle_vs_37687
Message: Request has failed with error code 9961697.
--------------------
Acronis Knowledge Base: http://kb.acronis.com/errorcode/

Event code: 0x000101F6+0x00070004+0x009800E1

--------------------

If you have not opened a ticket yet in the support (as opposed to a forum) you can do it while your subscription is valid (whether it's trial or paid). You can also configure reattempt in backup plan parameters, setting it e.g. to 300 reattempts , 5 minutes each. By default it is configured to 30 by 30 seconds, so network disruption for longer than 15 minutes will fail the task.