I cannot install my "Photo 926" on my Latitude E6500 with Windows 7 (64bit)

I'm using the current driver (Windows 7, 64 Bit, Version and get after installing the SW the following errormessage:
"The Dell Photo AIO Printer 926 printer is not installed. Please reinstall your printer driver."

I tried really everthing:
- Reinstalling Win7 => no success
- Used the DELLXPCleanUpUtility
- retried it with the compatibility-Option (Vista SP2) and administrator-rights