Notes about the 004 file extension:
Incorrect file associations could be the result of underlying issues within your PC system. As such it is highly recommended to scan your PC for invalid registry entries
, unused processes and other unfavourable system settings to identify slowdown issues.
The 004 file type is primarily associated with 'International S-57 Hydrographic Data' by US NOAA / US Army Corps of Engineers. A vector-based digital file containing marine features suitable for marine navigation. The file is based on the International Hydrographic Organization (IHO) S-57 standard. The file extension, ".000," for a base NOAA ENC cell is used for updating. The first update for a cell will be ".001" the next ".002" and so forth. The file extension .031 is used for catalog data (metadata) relating to the chart data.