What operating system are you using?
What happens when you try to install?
You are trying to install just photoshop or the cs2 creative suite?
You downloaded the cs2 installer from adobe just recently?
1.the system is IOS X EL CAPITAN.
2.the system start to install, but at the end failed and appear a message : error contact the technical support
3. just cs2
4. yes, I downloaded last week.
Unfortunately, photoshop cs2 will not work on El Capitan Mac OS X 10.11
Photoshop cs2 runs on macs with PowerPC processors and your mac has an Intel processor.
The oldest photoshop version that technically will run on your mac is phiotoshop cs3, though there could be issues since cs3 is from around 2007.
Your best option if you want a reliable photoshop is to subscribe to the Creative Cloud Photography plan that includes photoshop cc and LightRoom for around $10 a month.