There's nothing wrong with the license, and when I enter it manually in the license dialog it accepts it and everything is great. The next time I start the application it remembers most of the details, but always forgets the date (instead of an expiration date of December 31, 2049 it asserts my license expires on January 31, 2049). Since the date doesn't match what it wants from the serial key, it tells me my license is invalid. Once I change the month (which I can only do by advancing one month at a time in the date picker control instead of typing it in with the keyboard), everything is again fine. But is there a less tedious way of working around this error?

Pertinent information:

The software is the latest version available for download. So that's not it.

The OS, on the other hand, is ancient - it's XP SP3. It's also an Austrian German localization, which I assumed at first had something to do with the problem because, despite the application being all in English, the text file the license is stored in (with what appears to be .INI format serialization) uses the system locale to serialize the expiry date (the date picker control in the license dialog also appears to use the system locale, which makes the fact that it doesn't recognize the date even stranger). That decision results in the date in the text file appearing as "31-Dez-2049" instead of '31-Dec-2049" or "Dec-31-2049" or something else. I've tried changing this text by hand to "31-Dec-2049" and reloading the file (and this indeed works if I choose the file via Load again), but the next time I launch the app it still has the same problem. Or is the textfile in which I saved the license not used during startup, but rather some duplicate of the information stored somewhere in the registry? Will changing it there suffice?

Again, this problem doesn't break any functionality, but is nevertheless unnecessarily tedious.