RTL simulation on Quartus II

Dear all,

I am getting the following error messages every time I run RTL simulation from Quartus II software:

# -- Loading package STD_LOGIC_UNSIGNED
# ** Error: (vcom-11) Could not find altera.alt_dspbuilder_package.
# ** Error: C:/Users/nawad/Desktop/without_Detection/JustEqualiser/db/alt_dspbuilder_clock_gnf343oquj.vhd(7): (vcom-1195) Cannot find expanded name "altera.alt_dspbuilder_package".
# ** Error: C:/Users/nawad/Desktop/without_Detection/JustEqualiser/db/alt_dspbuilder_clock_gnf343oquj.vhd(7): Unknown expanded name.
# -- Loading package LPM_COMPONENTS
# ** Error: C:/Users/nawad/Desktop/without_Detection/JustEqualiser/db/alt_dspbuilder_clock_gnf343oquj.vhd(11): VHDL Compiler exiting
# ** Error: c:/altera/11.1/modelsim_ase/win32aloem/vcom failed.
# Error in macro ./FPGA_design_run_msim_rtl_vhdl.do line 9
# c:/altera/11.1/modelsim_ase/win32aloem/vcom failed.
# while executing

However, ModelSim simulator result was correct.

Any help would be very appreciated .
Regards,
Nadia