Acronis Backup 12.5: VM replication fails with "Failed to upload file '404'"

Symptoms

VM replication task fails with the following error message:

| error 0x194: Failed to upload file '404'.
| line: 0x7fe2b27b4a169899
| file: e:/212/enterprise/migration/vm_backup/http_file/impl/uploader.cpp:241
| function: Upload
| $module: disk_bundle_tape_off_glxa64_10130