A package server was failing to send basic inventories as well as package codebase information up to the Platform Server. The following squence of errors was observed in the agent logs:
PostFile to 'http://serverName/Altiris/NS/Agent/PostEvent.aspx' failed: HTTP error: (-2147209951)
Also the following entries existed in the Platform Server's IIS logs indicating "Bad Request" for all requests coming from that particular computer's address.
The package server computer was very low on memory resources. The physical memory was 1.9GB and the paged memory was 4x that of non paged. As a result the agent was not able to compose and or post a complete request to the Platform Server.
Restarting the computer recovered more memory for the agent and other programs vying for resources to function properly. After restarting the computer the agent was immediately able to post all of its cached events and inventory files.
It was also recommended that, in order to prevent future occurrences, to add more memory to the server and bring it up to 4GB.
Symantec Management Platform 7 SP5
Symantec Management Agent 7.0.8705.1703