Photoshop CS2 install blocked by previous CS5 files

If you're trying to reinstall CS2 in order to subsequently install the CS5 upgrade, there is no need to do that.

You can just install the CS5 upgrade (even on a device with no previous Adobe apps installed).

You enter the CS5 upgrade serial number then enter the CS2 serial number as a previous qualifying version. No CS2 activation will be required (which is not possible anyway). Just CS5 - which can still be activated.

In the absence of CS5 installation disks, you might try the link below.  However, there are no guarantees it will work with your license.  Follow the VERY IMPORTANT INSTRUCTIONS.

https://prodesigntools.com/all-adobe-cs5-direct-download-links.html

Failing that, these are modern replacement options:

Photoshop Elements or Premier Elements (approx $100, no subscription needed).
https://www.adobe.com/products/photoshop-elements.html

Creative Cloud Photography Plan (approx $10/month for 12 months). Includes the following:

• Photoshop CC and Photoshop on iPad
• Camera Raw
• Lightroom on desktop, mobile and the web
• Lightroom Classic
• Portfolio website + hosting
• Adobe Express (free starter plan)
• Bridge
• 20 GB cloud storage (upgradable to 1 TB).

https://www.adobe.com/creativecloud/photography.html

Premium Adobe Express ($10/month).

• Adobe Express app (web and mobile)
• Premiere Rush (desktop and mobile)
• Photoshop Express (mobile)
• Spark Video (mobile)
• Spark Page (mobile)
• Adobe Portfolio + Hosting
• 100 GB of cloud storage
• All premium templates and design assets including the entire collection of over 160 million royalty-free Adobe Stock photo collection.

https://helpx.adobe.com/express/using/express-overview.html

Creative Cloud All Apps (51 + apps & services) and Single Apps Plans
https://www.adobe.com/creativecloud/plans.html

Good luck!

As @John T Smith said, CS2 is dead. Impossible to activate.

• Do you have your original CS5 installation disks that you received at purchase?
• Do you have an older operating system that supports 12 year old software?
• Do you have a valid CS5 serial number?

If yes to all 3, you can run the Creative Suite Cleaner tool below to wipe old Adobe software from your system.  Restart computer.  Do a fresh install of CS5.

https://helpx.adobe.com/creative-cloud/kb/cc-cleaner-tool-installation-problems.html

Hope that helps.

=============
Beware of fake Adobe reps who may contact you privately offering to sell you software or take control of your computer. It's a scam, run away! Real Adobe employees will never reach out via Outlook, Yahoo, Gmail or Skype.
=============
3 Easy Ways to Identify Genuine Adobe Staff
https://tinyurl.com/10791730

CS2 is a dead product

The CS2-CS3-CS4 activation servers have been removed from service
-https://helpx.adobe.com/creative-suite.html?promoid=19SCDRQK
-So even if you have a disc or saved download, CS2-CS3-CS4 are completely dead
-Adobe also no longer supplies the special non-activation version of CS2-CS3-CS4