How do I change my MS Excel from 32 bit to 64 bit - Microsoft Community My OS is Microsoft Windows 10 Pro - so that represents a problem ? Hi Peter, not the operating system does not matter You can run an Office 32 bit on a 64 bit Windows or visa versa I mean Office type software, but that includes other associated software I have Windows 10 Pro 64 bit and run Office Professional 2021 32 Bit