If you receive an error about an "attempt to write a readonly database" when opening an OpenFlows model, it might be related to the Engineering Libraries file.
Deleting this file may resolve the issue. Here's how-
If you receive an error, while using a Bentley Hydraulics and Hydrology product, that references engineering libraries then the following steps will allow you to revert back to the original.
**Before performing the steps below please make sure to close the application**
1. Navigate to this location:
Windows XP: C:\Documents and Settings\<user name>\Application Data\Bentley\EngineeringLibraries\Windows 7 and later: C:\Users\<user name>\AppData\Roaming\Bentley\EngineeringLibraries\
2. Delete the EngineeringLibraries.mdb (EngineeringLibraries.sqlite for newer versions) and any .bak or backup files for this database file.
If you don't see the files or folders listed above, make sure they aren't hidden. In some instances, the …\AppData folder has a Read-only setting which will cause you to get an error that you are trying to open a Read-only database. Setting permissions on the AppData folder to Everyone Full Control will clear this error.
Here are the steps to do this in Windows 7:
3. Open the program
If the error is still generated, contact Bentley Technical Support and they can provide a clean copy of the engineering libraries file.
Error when opening: "System.TypeInitializationException"