When trying to open a model from an old version of StormCAD (.STM) or SewerCAD (.SWR) , such as version 5.6, 5.5 or 5.0, one or both of these problems is encountered:
1) The file cannot be browsed to in the file open dialog (the file type .swr .stm is not available in the files of type dropdown).
2) An error message is generated: "Database format not recognized or read-only. It could not be opened."
First, if the file type is not displayed in the file open dialog, type in the full path to the file in the box next to it. For example "C:\Examplefolder\exampleoldfile.swr". Alternatively, you can drag and drop the SWR/STM into the product.
For the error, this issue can be resolved by opening the 32-bit version of StormCAD, CivilStorm, SewerGEMS, or SewerCAD. You can find this by going to "C:\Program Files (x86)\Bentley\StormCAD" (or \SewerCAD for SewerCAD) and double-clicking on the StormCAD.exe or SewerCAD.exe file. You can also create a shortcut by right clicking on the StormCAD.exe file in the program files folder and choosing "Send to" > Desktop.
Once this is open, go to File > Open and select the .STM or SWR file (or drag-drop the file, if the STM/SWR file extension does not show in the file open dialog). Once the model file is saved in the current format, you will be able to work on the file in either the 32-bit or the 64-bit version.
If this still does not work or if you're encountering a different error when attempting to open the file, contact technical support.