Action 'Update' could not be performed on object 'Default Offline Address List'.

To fix this:

a) Open Adsiedit.msc
b) Browse to Configuration, Services, Microsoft Exchange, , Address List Container, Offline Address Lists
c) Open properties of the Default Offline Address List on the right
d) Change siteFolderServer attribute to the DN of the correct Public Folder e.g.

CN=Public Folder Database,CN=Databases,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=MAIL,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=CONTOSO,DC=com