Quartus can't start Fitter (can't load library error)

I have a problem with a Quartus Pro installtion:

Everytime I try to synthesis a project, the Fitter stage crashes with the following error:

Problem Details
Error:
Internal Error: Sub-system: ATCL, File: /quartus/ccl/atcl/atcl_root.cpp, Line: 987
-------------------------------------
Error found while sourcing: c:/intelfpga_pro/19.2/quartus/common/tcl/internal/init/fdrgn.pkg_info
-------------------------------------
ERROR: Can't load library: c:\intelfpga_pro\19.2\quartus\bin64\fitter_fdrgn.dll. The operating system reports the following error: The specified module could not be found.
 
 
Stack Trace:
     0x535d: err_report_internal_error + 0x2d (CCL_ERR)
     0xfe33: atcl_initialize_pkg_info + 0x4e3 (ccl_atcl)
    0x10dca: atcl_initialize_quartus_interpreter + 0xaa (ccl_atcl)
     0xf742: atcl_get_interpreter + 0x42 (ccl_atcl)
    0x2ddf6: ACF_MANAGER_STORAGE_REAL::ACF_MANAGER_STORAGE_REAL + 0x606 (db_acf)
    0x2501d: ACF_MANAGER::internal_open_create_project + 0x7bd (db_acf)
    0x2697d: ACF_MANAGER::open_project + 0x7bd (db_acf)
    0xe1954: QHD_ROOT_IMPL::open_acf_if_needed + 0xc4 (comp_qhd)
    0xe084e: QHD_ROOT_IMPL::initialize + 0x10e (comp_qhd)
    0x17e73: QCU::DETAIL::initialise_qhd + 0xb3 (comp_qcu)
    0x18028: QCU::DETAIL::initialise_qhd_and_perform_checks + 0x98 (comp_qcu)
    0x1816c: QCU::DETAIL::intialise_qhd_and_run_qexe + 0x6c (comp_qcu)
    0x290bc: qcu_run_tcl_option + 0x2ec (comp_qcu)
    0x19c58: qexe_run + 0x438 (comp_qexe)
    0x1ad8a: qexe_standard_main + 0x26a (comp_qexe)
     0x2052: qfit2_main + 0x82 (quartus_fit)
    0x14a08: msg_main_thread + 0x18 (CCL_MSG)
    0x160ae: msg_thread_wrapper + 0x6e (CCL_MSG)
    0x20fb0: mem_thread_wrapper + 0x70 (ccl_mem)
    0x13f8d: msg_exe_main + 0x20d (CCL_MSG)
     0x2918: __scrt_common_main_seh + 0x11c (quartus_fit)
    0x17bd3: BaseThreadInitThunk + 0x13 (KERNEL32)
    0x6cee0: RtlUserThreadStart + 0x20 (ntdll)
 
End-trace
 
 
Executable: quartus
Comment:
None
 
System Information
Platform: windows64
OS name: Windows 10
OS version: 10.0
 
Quartus Prime Information
Address bits: 64
Version: 19.2.0
Build: 57
Edition: Pro Edition

The file it can't load is where it should be.

What I've tried until now:

• Reinstalled Quartus (using both direct download and Download Manager)
• Installed it into another directory
• Installed it on another drive
• Excluted the Quartus directory in the anti virus software
• Deactived the anti virus software

... but nothing helped ...

What else could I try to fix this?

Thanks