On 5/6/2011 1:31 PM, Paul McNett wrote: > I allow my software and application data to be freely copied (make it easy > for paid > customers to do what they want). But there's a license file in the appdata > directory > that: > > 1) must be present for the application to start (if not, a screen prompts for > the > license, directing the user to the web page to purchase a key)
Yes, encourage viral distribution!! Definitely! > > 2) the applications checks the status of upon each app start, but if the > computer is > offline it allows a max. of 20 days to pass before saying "go online so I can > check > the validity of your license". I do something similar to this. > > 3) uses information coded in the license file to generate the company name, > city, > state, and phone number fields. This information, from the license, is what > gets > shown on screens, in reports, etc. So you can't just copy another user's > license > unless you want to represent yourself as that user. You also can't change the > values > in the (plain-text) license file because the software looks at the hash and > compares > it with the encrypted hash in the same plain text file. Change one character > in the > license file, and it is no longer valid. Similar strategy here too. > > We control the validity of each license on our servers, and can turn them off > and on > at will. In our case this software is free to customers above a certain > purchase > volume that are in good standing. If they are late on a payment we've found > that > invalidating their license results in a check going into the mail > immediately. I > don't think anyone's yet figured out that they could last 20 days on a bad > license by > just unplugging the internet when the app starts. > > Paul I did the exact same thing back in 2005 when some SOB thought he was going to stiff me for around $4000. Several here warned about the legality of my actions, but I looked upon them just like the power/electric company shutting off my electricity for non-payment. Long story short: his IT person tried everything to defeat my interdiction. They had at least 80+ login attempts that day. He eventually paid. To this day, it's one of my greatest pieces of code written. That, and the auditing code I wrote back in 2001 to show that some dude was lying about using my software and finding bugs. hahahahaha -- Mike Babcock, MCP MB Software Solutions, LLC President, Chief Software Architect http://mbsoftwaresolutions.com http://fabmate.com http://twitter.com/mbabcock16 _______________________________________________ Post Messages to: [email protected] Subscription Maintenance: http://leafe.com/mailman/listinfo/profox OT-free version of this list: http://leafe.com/mailman/listinfo/profoxtech Searchable Archive: http://leafe.com/archives/search/profox This message: http://leafe.com/archives/byMID/profox/[email protected] ** All postings, unless explicitly stated otherwise, are the opinions of the author, and do not constitute legal or medical advice. This statement is added to the messages for those lawyers who are too stupid to see the obvious.
