Why dont you show us what you have and maybe ask questions about what you dont understand? We aren't going to do the homework for you.

For the love of god surround that in code tags...

BTW, not all code paths return a value means:

Your methods do not return a value in EVERY scenario. There are some scenarios that do not return...

probably wont fix it, but if you're using a messagebox and getting the result from it, you should use the DialogResult property. It would be something like this...

DialogResult dr;
dr =...

no the real problem is that you're using a variable before it exists. which is what Narue and I said.

BaseToken is returning a child classes variable (tokenValue), which it doesn't know exists because it's the Base class. The base class should declare the variable.