NullPointerException when attempting to execute 'Update Maven Configuration'

Certain Maven projects give the following error when I try to execute 'Update Maven Configuration':

An internal error occurred during: "Updating Maven Configuration".
java.lang.NullPointerException

The message returned is not very helpful in terms of where I should look to address the problem hence I'm a bit stumped on this one. Does STS write to a log anywhere? I'd be happy to provide more specific information if I can identify where the log is written to?

Cheers,

Edd