NT and NETBios Issues

So, I filtered ports 137 and 138 on my VLAN so that I can get rid off the constant browser elections (using IP helper address in the cisco gear to forward the udp broadcasts). This worked, but now users also cannot authenticate anymore. MS did not say that in their article(s) dealing with the browsing issue(s). Does any one have any suggestions how to solve the browser announcement issues WITHOUT killing other MS services ?

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