Some problems have been reported to run Chess Tiger 14 together with Chess Tiger 15. We have investigated this and found the reason it is so problematic, is the naming of the engines. They are all called chesstiger.dll and tiger.dll. Because of this windows gets confused as to which dll to load. In order to run the chesstiger 13 or 14 engine toghether with Chess Tiger 15 we have made the following workaround procedure: Step by step: 1. Download the fixtiger14.zip from the downloads section. 2. Salvage the tiger 14 engine files and book from a tiger 14 installation. You can either start from scratch or use another pc to install 14 on. Don't install it after you have installed CT15. Copy the following files to a save place: - chesstiger.dll - tiger.dll - chesstigerg.dll - tiger_g.dll - ct.tbk In principle you can now get rid of the tiger 14 install. 3. Install CT15 and check that this works. 4. Create a new directory below the ..\engines directory and call it tiger14. 5. Copy the files from step 1 into that directory. 6. copy the fixct14.exe from the zip file to the same directory. Open a command prompt and go to that directory. Run the fixtiger14 program, it will ask your confirmation, type a uppercase 'Y' and press enter. The result will be that chesstiger.dll is patched and renamed to ct14.dll and tiger.dll to ct14e.dll. 7. Now register the engines in their new loctions, either use the engine wizard to import ct14.dll and chesstigerg.dll or open a command prompt, goto the tiger14 directory and give the following commands: REGSVR32 ct14.dll REGSVR32 chesstigerg.dll Thats all.