Thanks so much for your response. Yes, I tried running Multiple Ring Buffer again without the 'Dissolve All' option checked and the process did execute, but there is still a problem. Although the output layer shows two buffer distances (.25 and .5), in the attribute table there is only one distance listed (.5). So I don't think I can use the 'Dissolve' tool to fix my problem because I do not have a field to base the process on. I have attached a photo of the attribute table and screen... any ideas of what to do?