Issue: Lightroom 2.0, refuses to start, crashes, stalls, freezes, produces system errors, etc.
Solution: There are a number of possible causes for above problems, which are too numerous to cover in the space provided. However, Adobe have provided a number of troubleshooting documents:
Troubleshooting information for Photoshop Lightroom when using Mac OSX
Troubleshooting information for Photoshop Lightroom when using Windows XP
Troubleshooting information for Photoshop Lightroom when using Windows Vista
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