I too am having this same issue. I'm trying to load the UnderDogs Install on an actual PII 266 Mhz PC running Win98SE, and have received the same error. The install was Underdogs -> Manalink 2.01 -> CardArtNew -> jatil 5/13/09 update -> CardArtUpdate. The same setup is working flawlessly on my WinXP SP3 box and I couldn't be happier! The original Microprose MtG Manalink 1.32 has run on my little PII 266 box for years and years, I was just hoping I could run these new updates on older Win98 systems also.
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I've played MtG (on and off) since before Arabian Knights, and was thoroughly addicted for the first 5-6 years (time and money-wise) and I purchased the original Microprose MtG when it came out. I've literally been playing this game on a near daily basis for well over 10 years now, and only last week did I think to Google for an update. Not only had the Manalink version gone from 1.32 to 2.0, with the inclusion of tons of new cards and mechanics (bestill my heart), but I find this wonderful forum where a small team of coders have be able to open up even more of the program... along with wondorous possibilities. I'm sure you've heard this all before, but Dude... YOU GUYS ARE HEROES! I've always felt the Microprose software to have a good, comfortable GUI and so far, the updates work seemlessly. This is now my daily go-to spot were I look for updates, I'm totally stoked about how much has been done. Even if development ceased tomorrow, there is already enough to keep me happy for another 10 years!
Congrats and Endless Gratitude to all Coders, Scanners, Testers, Mods, Artists, Hackers, Thinkers and Doers... I am forever indebted to you.
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Gush --