I ran into an issue where as Outlook client experiencing slowness when accessing Public Folder on Exchange Server 2010. I was facing 2 different issues at 2 different geographical location, users at Europe were experiencing slowness when trying to access Public Folder via Outlook and Users in US where getting credential prompt when it failed to connect to default Public Folder Database.

I was able to fix Outlook slowness issue while accessing the Public Folder by making the registry changes on Public Folder Server, as Outlook client were trying to connect to Public Folder Server which were in US.

I followed this article and applied Method 2 to fix the issue.

But, the issue at US location was Outlook client were prompting for credential when trying to connect Public Folder Database which was not a Default Public Folder Database on Mailbox Database. So to fix this issue I had to apply the same registry fixes but I also had to install Hot Fix on Public Folder Server. Hot Fix is part of Method 1, but this article doesn't have a link to download the Hot Fix.

I had to call Microsoft get this Hot Fix which you can download from here. Writing this article, so that you don’t have to call Microsoft to get this Hot Fix.

I hope it helps.

Cheers,