GUIStudioMDL error

When I’m compiling models with GUIStudioMDL, there always the same error, which stopping all compilation process.

writing c:\program files (x86)\steam\steamapps\username\half-life 2\hl2\models/TAI\heavy_combine\01AR_combine_soldier_old.mdl:
Error opening c:\program files (x86)\steam\steamapps\username\half-life 2\hl2\models/TAI\heavy_combine\01AR_combine_soldier_old.mdl! (Check for write enable)

Another example

writing c:\program files (x86)\steam\steamapps\username\half-life 2\hl2\models/Characters\Jessica\Jessica.mdl:
Error opening c:\program files (x86)\steam\steamapps\username\half-life 2\hl2\models/Characters\Jessica\Jessica.mdl! (Check for write enable)

I can’t understand, what’s wrong. In the examples I used simple models from Garry’s mod, not even a headhacks.

I don’t remember exactly, but I think it’s because you didn’t create neccesary folder ("/TAI" in first case and “/Characters\Jessica” in the second).

Yes, you right. I’ll test on the headhacks models. Thank you!