Hi There,
I realize you said "Hyper-V" but the behavior you're describing sounds an awful lot like an issue that caused me some pain with VMWare ESX.
Basically, 0x0035 code was undocumented in the official VIX API reference, but I found references to it meaning that an invalid Data Store name was specified.
Which turned out to be true. If there is a period of time that goes by between importing the Virtual Machine, and attempting to use it, the data store where it lives (and the path to the VM stored in the project file) can change on you. The mismatch causes the undocumented error code.
I believe there is no such concept of data stores in Hyper-V. However, it is worth mentioning, since except for that it sounds exactly like what I ran into previously. Hope this pans out to be useful.
--Cary