VM's disk capacity required for uploading runtime process

[Yuya]

Hello,

The backup job failed with the following error.
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Processing FJKAP01 Error: Cannot upload guest agent's files to the administrative share [\\10.90.1.11\ADMIN$]. Cannot copy file. Source file: [C:\Program Files\Veeam\Backup and Replication\Backup\VSS\VeeamGuestHelpers\VeeamGuestHelper_X64.exe]. Target file: [\\10.90.1.11\ADMIN$\VeeamVssSupport\VeeamGuestHelper.exe]. CopyFile() failed. Win32 error:There is not enough space on the disk. Code: 112
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Because the disk capacity of the guest OS to be backed up is insufficient, uploading of the runtime process has failed.
How much disk space is required on the guest OS to succeed in backup?

Regards,
Yuya

[foggy]

Not much, the package itself is about 1 MB, so this guest should be extremely low on space.