That's about what I expected, but it's crucial to actually have the error text.
The DeviceNet Tag Generator Utility accesses both the *.DNT and the *.ACD file and modifies them both, so the crash could have a complex cause.
Certainly a reinstallation of the DeviceNet Tag Generator Utility can't hurt. You can download the current release by starting at the RSI Download page:
http://www.rockwellautomation.com/rockwellsoftware/downloads/
Select Downloads / Utilities / RSLogix and then Search. The Tag Generator will be the fourth link.
That will be "Build 87", i.e. 1.0.87. This has a couple of updates over the 1.0.77 that was shipped on the RSLogix 5000 17.00 DVD.
While it does not affect you, there was an issue with the DeviceNet Tag Generator and RSLogix 5000 v18.00 , 18.01, and 19.00. The details are in Knowledgebase document
114654.
I noticed you're running RSLogix 5000 17.00. While this editor is fine, the firmware that shipped with it on DVD had a CIP connection fault mode bug that was fixed in firmware 17.03 or so with most controllers. See RA Knowledgebase
Article ID 62845 for those details.
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