If you deploy NAV Client using ClickOnce technology and experience slow performance, especially when posting or reporting, please check with your IT to see if your organization deploys roaming profile policy for user workstations. ClickOnce version of NAV does not work well with roaming profile.
Roaming profile policy will configure the workstations and/or servers to store user profile folder on a network drive/storage, instead of save them on their local drives. ClickOnce technology deploys NAV Client into user profile folder (i.e. AppData). If this folder is stored on a remote location, the NAV application will be there as well. This results in slow performance of the software, since it is running from network, instead of from local drive.
Bottom line, do not use ClickOnce to deploy NAV Client if you have roaming profile policy applied throughout your organization.
Microsoft also has an article related to ClickOnce deployment in roaming profile situation: https://support.microsoft.com/en-us/kb/2571899.