Can I restore a backup of my projects? Is there a way to recover model files?
This will depend on the circumstances you are encountering. Below are some possible solutions
A .BAK file is a backup file. This backup file can be for any of our programs file types. The backup files provide some insurance just in case something happens to one of the other files. For example, if you have a WaterGEMS model you might have a backup file for the .WTG, .WTG.SQLITE, and .WTG.DWH. These would be .WTG.BAK, .WTG.SQLITE.BAK, and .WTG.DWH.BAK. There are also backup files for program files such as flextables or queries. These files can be found in the software's program files folders. One example is a the "predefinedflextable.xml.bak" file, which is located at "C:\ProgramData\Bentley\WaterGEMS\10" for latest CONNECT Edition software.
Also, note that backup files might have a number associated with them if there are more than one .BAK file. For example, .WTG.01.BAK.
Whenever a file is saved, the previous version is retained, in the form of these .BAK files. If you need to recover the version of your model before you last saved it, you can copy the model files to a new folder and remove the ".01.bak" extensions. You will need to alter at least the starter files (.WTG, .STSW, etc.) and the database files (.WTG.SQLITE, .STSW.MDB). Once completed, you can open the file normally.
Note that you can control the number of backup "levels". Basically by default, one backup level is used, which is why you see .01.bak files. If you chose to have two backup levels, the previous two revisions of the model will be retained, with .01.bak and .02.bak extensions. To configure the number of backup revisions, go to the Tools menu, click Options, click the Global tab and modify the "Backup Levels" field.
If the program was unexpectedly interrupted (for example power failure, crash, etc.) and the file was not saved, you should still have the 'main' model files (.STSW and .STSW.SQLITE for current versions of the storm and sewer products; .WTG and .WTG.SQLITE for current versions of water products), which should reflect the last saved version. In this situation, if you are looking to try to restore the model you were working on when the interruption occurred, you may be able to find it in the Windows temporary folder.
Basically whenever you open a model file, the main files are copied to a location within Windows's temporary folder. When you are working on the model, the changes are being written to that temporary copy. Those changes are only committed to the model folder, or the location where the model is stored, when you save it. The files are moved from the temporary location and overwrite the old copy in the location where you stored the model.
If the program is not closed properly, the copy of the model may be left behind in the temporary folder. The location of this folder depends on your operating system and Windows user, but a shortcut would be to type in '%temp%' in the Windows Explorer address bar. This will bring you to the main temporary folder. Within this, navigate to \Bentley\PROGRAM_NAME\ (where "PROGRAM_NAME" is the name of the program you're using, such as StormCAD or WaterGEMS). You may want to sort the contents of this folder by date modified, then look for the name of your model file. Try copying the model files ending with .$$$ to another folder on a local drive. Then remove the .$$$ extension and try to open the model.