Applying regular patches is vital for the timely correction of security vulnerabilities, but installing patches also risks disrupting working systems by potentially introducing unknown errors. System administrators must manage the challenges of patching using a combination of reliance on best practice and available information to best match their organizations' needs. In this work, we study how patchrelated activities are supported by the mailing list of the website PatchManagement.org which is dedicated to the task. We qualitatively coded 356 list emails sent between March and July, 2018, to understand how members interact with the list community. Based on our results, we argue that the mailing list is an example of an Online Community of Practice, where practitioners engage in communal learning and support. We find that the community supports members in multiple phases of the patching process by providing workarounds before a patch is available, guidance prioritizing released patches, and helping with post-patch trouble. Additionally, the community provides help around tool selection and facilitating discussions.