When constructing URLs to access the Web Storage System it is common practice to use the domain name after the backofficestorage part of the URL. This part of the URL should match the root folder of the 'M' drive (IFS) and is actually derived from the default recipient policy and not the domain name. If the default recipient policy were to change then any application using the domain name to construct the URL would fail. I came across this issue when installing an E2K server into a 5.5 site in which case the default recipient policy is taken from the 5.5 system. If you want to see this in action just change the default recipient policy, restart the Information Store and then look at the M drive. The root folder name will have changed to reflect the new recipient policy!