You can download the latest version from the HEC web page:
The following is a list of bugs that were found in version 5.0 and fixed for version 5.0.1:
1. Unsteady Flow with Pumps: A pumping station that is connected "From" a storage area had a bug that could generate an "access violation" error.
2. Unsteady flow with rating curves at structures: The rating curves for: inline structure outlet rating curve, lateral structure outlet rating curve, and user defined gate rating curves (both inline and lateral) have been changed so that unsteady will no longer extrapolate past the top or bottom of the curve. A warning will be generated the first time this happens.
3. Unsteady flow with an SA/2D Hydraulic Conn between two 2D areas: There was a bug when a SA/2D connector has a 2D area on the upstream side. This bug would sometimes show up as an "access violation" error.
4. Steady Flow Analysis (Encroachments at Bridges): There was a bug when type 1 encroachments were specified immediately adjacent to a bridge opening. The encroachment was being set to the opening. The left encroachment was set to the left side of the bridge opening and the right encroachment was being set to the right edge of the opening.
5. Unsteady flow with 2D areas/Internal Hydraulic connector: For a hydraulic connector inside of a 2D area, the DSS output for headwater and tailwater had a bug. The reported values were "one cell" away from the intended values. For a connection that was entirely inside of a single cell, this resulted in a reported water surface of "0.0". This was only a reporting issue.
6. 1D Velocity plotting in HEC-RAS Mapper for metric data sets: 1D HEC-RAS Mapper maximum velocity plot was wrong for SI data sets.
7. Unsteady flow Lateral Structure connected to a 2D flow area: For a lateral structure connected between a 1D river and a 2D area, the lateral structure was pulling the water out of the river at the wrong cross section location. The flow was being re
8. User Interface – Right Bank of Main channel: If you had a cross section with a vertical wall at the right bank of the main channel, the interface was displaying the main channel bank station at the bottom of the vertical wall. The computations were correct, this was just a visual problem in the interface.