As an addendum to this, the following excuse has appeared in a some non-Mac fora, cited as coming from <http://www.macintouch.com/>. The interesting this is that it sounds like rubbish, but has been entitled in one location as a "Mac Year 2004 bug" (it's really a Canvas bug, if it is true).
> After contacting Deneba.com (now owned by ACD Systems), we've received > detailed info about this Canvas 3.5 Mac "Year 2004" bug : > > To make a long story short, Canvas maintains a counter for date/time > settings. In the Mac architecture, the theoretical start date for > all clocks is 1904. All times from there forward are measured after > 1904. As this value increases in size, it reached the limit in terms > of the allotted length for that string in the Canvas 3.5 Mac code. > Once it hits that limit, it begins to count in negative numbers, > thus triggering a Canvas expiration. > > The existence of the dialog box regarding an expiration is because > the installation code for Canvas 3.5 was the same code used for > trial, NFR, and Beta versions. So when the date count flips to > negative because of this bug, Canvas is considering that negative > date to reflect that it's a trial/NFR/beta copy and is expiring it. > > Interestingly, we believe this same thing could happen on Windows, > but because Windows has a clock start date of 1970, the problem > wouldn't manifest till 2070. Now, anyone who's done computer programming with dates on a Mac will know that the counter in Mac OS 9 and prior runs from 1904 to 2040 (i.e. about 136 years), not 1904 to 2004! The claims made in the quoted text do not explain why Canvas is "maintaining a counter for date/time settings", let alone why it is storing "a string [of numbers]" limited to 100 years. This sounds like a classic "Y2K" problem that bears no resemblance to Mac OS. It sounds like a unique Canvas-specific programming error, not a bug in Mac OS or Windows. Normally, dates are stored in "binary", not as "a string", so they do not expire at exactly 100 years (some, for instance, expire after 68 or 136 years). > Unfortunately, according to the same source, since "the source code > and compilers for 3.5 are not accessible at this time to allow any > patches" the only workarounds are: > > * use the mechanism for exporting files out into other formats > (the EPSF format is really effective while exporting to > Illustrator) > * rolling the Mac clock settings back (only a temporary > workaround) I wonder if there are any "cracked" copies of Canvas 3.5.5 available...maybe some of them bypass the Canvas "date/time counter". > As a more long-term solution Deneba can only recommend an upgrade to > Canvas 9 (which will open all Canvas 3.5.4 or higher files > directly).
