Lucky me… i ran into an issue while trying to get the Office 2010 web applications installed and running in our new SharePoint 2010 beta farm. We are setting up the farm with domain service accounts and we are using a dedicated service account for the office web application services application pool.
The issue we were experienceing was when trying to view a word document or powerpoint presentation in the browser it would display the office web application, but when converting the document or presentation and storing it in the cache site collection it would fail with non specific errors. Errors such as the network connection was unavailable or an error occured in application please open in the client application.
The ULS logs, windows application event logs nor the errors I was recieving were giving me any hints as to why the documents would not convert and open in the office web application service. I was essentially out of options. I started working with a Microsoft MCS guy who provided the ULS logs to a member of the SharePoint product team for assistance and low and behold it was a local security policy privileges (undocumented) which were not provisioned for the domain sevice account used for the services.
The privileges in which the account running the office web application service application pool needs to be a member of is “Replace Process Level Token” and “Adjust Memory Quotas for a process properties“.
These privileges are normally setup automatically if the account you are using to install the office web application bits has permissions to add members to the local security policy privileges. In my case the account i was using did not have these permissions.