is there a way to rename the device so it does not appear as 'Teensy USB Serial' in device manager ?
Yes, there is a way, but it's not free. You will need a code signing certificate. This is the best place I've found.
https://www.ksoftware.net/code-signing-certificates/
The cheap OV type is fine.
Once you have your code signing cert, then edit CDCACM.INF (or course you can edit this file all you like... but Windows will not use it without a matching & properly signed .CAT file). Near the end you'll find these lines. Change them to whatever you like!
Code:
[Strings]
MFGNAME="PJRC.COM, LLC."
DEVNAME="Teensy USB Serial"
The main complication you will encounter is use of Hardware-id vs Compatible-id. PJRC's "CDCACM.INF" uses these lines to match to devices:
Code:
[DeviceList]
%DEVNAME%=DriverInstall,USB\Class_02&SubClass_02&Prot_01
[DeviceList.NTamd64]
%DEVNAME%=DriverInstall,USB\Class_02&SubClass_02&Prot_01
By default, Microsoft's tools will not allow you to sign this. The easiest solution is to change this to match to vendor and product id, instead of class, subclass, protocol. Or you can try to work around the tools... but that is very difficult and as far as I know there are no tutorials or examples anywhere. You can find numerous sites and examples for INF files using hardware id matching.
Microsoft's tools are part of the free (but enormous download) Windows Driver Kit. You don't need the rest of the WDK, but as far as I know that's the only way to get the 2 small command line utils.
First you run INF2CAT, to create an unsigned .CAT file which matches the .INF file. Then run SIGNTOOL to sign the .CAT file using your code signing certificate.
Years ago PJRC stopped distributing the raw .INF file. Most Windows users prefer the installer. While it is possible to install the .INF without an installer program, our experience was many users got stuck trying to install it manually. It became too much of a tech support burden, and created a barrier for many Windows users. So we no longer distribute the raw .INF and .CAT files on the PJRC website.
After you've run the Teensyduino installer, you can find it somewhere in C:\Windows\inf (which is a hidden folder). But Windows renames it to an auto-generated "oem" name, so there's no simple & easy directions I can give you. Instead, I'll attach a zip file with CDCACM.INF and CDCACM.CAT which the Teensyduino installer uses when you install into Windows 8 or earlier.
But remember, after you change anything in the .INF file, you must create a new .CAT file with a proper digital signature. You must have a valid code signing certificate to create the signature.