[thincom2000]

This could be a number of things. I have recently seen a similar problem if the mod was installed when vB's sessions table was already full. This would cause database errors on every page load due to a memory overflow. The only way to fix it would be to restore a backup and manually cleanup your sessions table or to increase MySQL's max_heap_table_size and restart MySQL (you would have to do this even if you never install VaultWiki). Then you should be able to install successfully.

However, if you're not seeing database errors in your logs, it's possible you are somehow getting VaultWiki Lite's own blank page issue to occur during the install process. You should be far enough along to access the AdminCP and perform the required install steps in the Namespace Manager which get rid of this error. Once you have done so and you see regular forum pages back, continue the install steps from step 8 onward.

If it's neither of these, something else is going on but you should be able to find more information by looking at your logs.