serialo: Parameter „serialo.fileType" has invalid value „thinprint" after update to Fusion 13.5

[lhaeger]

So I updated to 13.5, started an Win 10 VM that was running just fine in 13.0.2 and get this error (in German) :

"serialo: Parameter „serialo.fileType" weist einen ungültigen Wert „thinprint" auf."

Looks like 13.5 dropped support for this value (or added a check that 13.0.2 did not have). What's the background to this? Why do I have "thinprint" in the vmx anyway (never printed anything from that VM, nor set up printers, IIRC).

If an update drops a feature, it should know about this and handle the case by itself. Or at least suggest a solution or workaround (delete from vmx? change to what other value? Any consequences inside the VM? ...). Not just pop a technical error in my face...

[Technogeezer]

Agree that VMware dropped the ball on this. They buried the notice that ThinPrint was being removed in the 13.5 release notes and did not advise anywhere else. The Tech Preview that just concluded didn't even give us a clue that the feature was being removed.

My suspicion is that the capability was included in the virtual machine configuration by default if you created a virtual machine with Fusion, awaiting you to turn it on if you wished. 

The workaround is to edit the .vmx file manually and remove the lines that reference serial0 (two of which have reference to "thinprint". 

Then use other means to configure printers. If you're on a bridged network, Windows should be able to find any networked printers. If you're on NAT networking, try enabling printer sharing for printers defined on your Mac. Windows should be able to pick those up automatically.

[ingsings]

I am experiencing the same startup error as the OP.

Unfortunately in 13.5 it appears that most of the .vmx file contents are encrypted and so not editable in a text editor. I've searched the VMware KB for suggestions given the encryption but haven't found any.

Do you know how to edit a 13.5 .vmx file? Thanks.

[Technogeezer]

What type of encryption did you use? If it’s full encryption, the entire VMX file is encrypted. You’ll need to decrypt the VM before editing the VMX file manually.

With the partial encryption options (the Fusion 13 partial encryption and the broken Fusion 12 experimental encryption) the VMX file is not encrypted (there are individual entries that look like they might contain encrypted data but don’t touch them). You can edit the file manually after you’ve shut down the VM and Fusion. 

[ingsings]

Decrypting the VM was the trick - thank you!

I had to first remove the vTPM in order to decrypt. This wasn't a problem with my Windows 10 instance (which doesn't require a TPM module). It may be tricker with my Windows 11 instance (which does require a TPM module) but I'll give it a try.

I don't recall why I encrypted my VMs given they don't contain sensitive information. Something fun to try I guess!

Thanks again.

[ingsings]

FWIW: I now remember why I encrypted my Windows VMs.

Windows 11 requires a (virtual) TPM (Trusted Platform Module). Fusion requires an (at least partially) encrypted VM in order to add a vTPM. So when I upgraded to Windows 11 I encrypted my VMs.

[Technogeezer]

If you do re-encrypt the VM, unless you have a really, really good reason (whic most do not)  use the option to “encrypt only the files needed to support a TPM”, I.e. partial encryption. That will allow you to add the TPM but not pay the performance penalty of an encrypted virtual disk.

I’ve removed the TPM from a Windows 11 VM to decrypt and re-encrypt. I added it back after re-encrypting and the only ill effect I had was having to re-validate my login (I use Windows Hello with a PIN to log into the VM.).

the sticky part of losing a TPM comes if you have Bitlocker enabled in the VM (which few people do). Then it becomes an exercise in Bitlocker recovery that you have to prepare for, but that’s a Windows specific task and nothing to do with Fusion. 

[ingsings]

"use the option to “encrypt only the files needed to support a TPM”

That's exactly what I chose, and it all worked fine without any ill effects to my Windows 11.

Thanks again!