Unrealistic forces and moments in columns and beams

[Anonymous]

i have developed a model of building in RSA and i am getting proper results in model if supports are modeled as pinned, the moment i save the file and change the supports to springs member forces are shooting up like any and running in billions kN. what might be the reason for this surge/spike in forces. 

[Rafacascudo]

You probably have instability warnings that cannot be ignored. 

Can you send the mode?

Zip it before attaching