Is registration required?
vDos is freeware for most users. It will however check if the PC is joined to a domain, or files on a network drive are addressed. Only if so, the About popup is then displayed every three hours of continuous use. So vDos is also commercial software for targeted business users. A registration or donation would of course still be appreciated, even if the popup/nag doesn’t apply.
What will it bring?
That nag won't popup anymore. You would contribute to rewarding the countless hours invested in vDos, further development and support; keep vDos nag-free for most users? You'll be informed of new versions. Some two weeks after the initial release, so eventually reported bugs will be fixed. Registered users however generally don't care about new vDos versions. The current one obviously does the job… I could be more open to your specific issues or wishes, and supply an intermediate pre-release to address those.
What about new versions?
Registration is lifetime and valid for any new versions. If I would decide to change this policy, it won’t affect existing registrations. This is of course no sound business model, while licensing vDos will even die out in time. vDos is however mostly a paid for hobby, so I can commit myself supporting it. As long Windows supports 32-bit applications on x86/64 based PC’s, vDos should just continue to work. Future support shouldn't even be required. To be real safe, a 64-bit version will be available for registered users with the next (2020) release.
How to register?
After filling out the registration form, you’ll receive an email with an invoice and license file (if paid directly by Stripe). The license file is to be copied to the vDos directory. That’s it, no activation procedure or online validation involved. Transferring a registered vDos to other/new systems still remains a mere copy of some files (plus one).
vDos can be registered in two flavours, they only differ in what vDos eventually validates:
Username: € 40 per username.
The Windows username has to be (one of) the username(s) defined in the license file.

Network: € 200.
Unlimited users, as long the PC’s are joined to the registered domain or that network drive is addressed.

The required username or network ID is shown in the nag, the vDos window System Menu - About, or issuing the
ABOUT command at the vDos/DOS command prompt.
Money back guarantee?
No, you can (should) evaluate vDos for as long you need to be confident it will fulfill your requirements. Once issued vDos licenses can’t be revoked since there is no online validation.