Consider yourself fortunate. It is actually a very good thing that you were unable to connect to your database with version 12, given that the server and all of the other clients are connected to it with version 11. When you run different releases of [any] version on various machines that are all pointed to the same database, you will get weird, voodoo-like performance from the software and you risk corrupting the data beyond repair. Such corruption can cause functionality issues that cannot be resolved.
The reason you ran into this issue is that version 12 requires that the server/computer hosting the data be running Firebird 3.0 but in your case, the server/computer hosting the data is running Firebird 1.5.
As I see it you have the following two options...
Option 1: Uninstall version 12 and reinstall the same iteration of version 11 running elsewhere on your network so that they all match.
Note: We only have two version 11 installation files that we can send you. they are...
Option 2: Install version 12 over the top of version 11 on your server and the other clients so that they match what the new client is running and so that the new client will then connect to the data.
If you select Option 1 above, you must do the following...
1. Go to a working client and go to C:\ProgramData\Gradience and copy the Hrware.ini file and save it into a neutral location accessible to you from the NEW client.
2. At the NEW client and go into Services on the [new] client and stop Firebird. The software does not [use] it. It [uses] the 1.5 Firebird that runs on the server/computer hosting the data. Nevertheless, we don't want to complicate things for version 11 when you install it there.
3. Try to uninstall Firebird 3.0. If you don't find it listed just move on to step 4.
4. Go to C:\ProgramData and delete the firebird folder.
5. Go to C:\Program Files (x86)and delete the firebird folder.
6. Go to C:\Program Files (x86)and rename or delete the Gradience folder
7. Go to C:\ProgramData\Gradience and replace the Hrware.ini file with one from another working client.
8. Install the appropriate release of version 11 from the list below.
Click here to install version 11.0.1508.12. for Gradience Attendance & Records
Click here to install version 11.0.1508.12. for Gradience FMLA Tracker.
Click here to install version 11.0.1508.12. for Gradience TimeClock. Use this for TimeStation too.
Click here to install version 11.0.1508.12. for Gradience Web TimeStation. Enterprise Only
Click here to install version 11.0.1606.29 and select the particular title(s) during installation.
If you select Option 2 above, you must...
1. Go to the server/computer hosting the data and click here to install the latest version..
2. Go to each existing client and install version 12.
3. Leave version 12 on the new client but it's ini file must match the ini file from a working client.
If you ever have any issues where the software fails to connect to the data, please click here.