Intel HPC Toolkit 2021.10 or 2023.x

[PoonamSharma]

I am trying to build VASP5.4, which requires the classic Intel Fortran compiler (ifort) and is not compatible with the newer Intel oneAPI HPC Toolkit 2025.x.

Could someone please guide me from where I can download these older HPC Toolkit versions?

Thank you in advance!

[Ron_Green]

We have been working with VASP for enabling our latest compilers. The latest VASP versions should work with our new compilers.  

Should you have an older VASP version: read the notes at the top of this Forum about "Older Compiler Download Information" 

[PoonamSharma]

Thank you for your response.

I did attempt a build of VASP 6.4.3 (newer version) with the recent oneAPI 2025.2.1 toolchain, the compilation was successful and executables were generated, but at runtime in the OUTCAR file I have different iterations for my calculations, while in the OSZICAR file no iterations are written.

So, I shifted to VASP 5.4.4, which (as far as I know) still requires the classic Intel Fortran compiler (ifort) and does not work reliably with the newer ifx compiler from the latest oneAPI 2025.x releases.

[JohnNichols]

Could someone please guide me from where I can download these older HPC Toolkit versions?

When you start using OneAPI, you start with a fresh install at that time and that set of programs. There is no going back to earlier versions unless you have paid support. You should always update using the Control Panel updater as that keeps the old versions from your start date. 

The program that is the furthest along is Visual Studio and it updates weekly now, plus 2019 is not available without a subscription, 2022 Preview disappeared this week and 2026 is now supported with 2022 only. Oneapi updates about 3 to 4 times per year and is about 8 months behind the latest VS.  So something like VASP will be further behind.  

This is all you get, you just have to do what we all do and work with what we have got now.