Checking the web proxy settings for any bandwidth limits or filtering rules that might be affecting performance When facing slow performance issues with Tableau Server accessed via a web proxy, the initial step should be to check the web proxy settings. Look for any bandwidth limits, filtering rules, or other configurations that might be impeding the data flow and affecting performance. Adjusting these settings can often resolve performance issues related to proxy use. Option A is incorrect as disabling the web proxy might not be feasible due to organizational policies and does not directly address the root cause. Option C is incorrect because reinstalling Tableau Server is an excessive step before checking proxy settings. Option D is incorrect as changing the port used by Tableau Server might not be feasible or effective in addressing performance issues related to proxy settings.