How to fix the product expired problem in Adobe Photoshop?

Are you getting this error while opening Photoshop CS3 or Illustrator CS3
“Product License Has Expired”

1. delete cache.db in “c:Program FilesCommon FilesAdobeAdobe PCDcache”
2. Run the adobe cs3 product
3. enter the products key for adobe cs3 product
4. set read-only attribute for “c:Program FilesCommon FilesAdobeAdobe PCDcachecache.db”
5. Click “Next”

6. remove read-only attribute for “c:Program FilesCommon FilesAdobeAdobe PCDcachecache.db”
7. “Never register” in Product registration from
8. set read-only attribute for “c:Program FilesCommon FilesAdobeAdobe PCDcachecache.db”
9. Complete

PS: if you need to activate another Adobe CS3 product, please do the same thing like above except for the step 1.
Replace the step 1 by
1. remove read-only attribute for “c:Program FilesCommon FilesAdobeAdobe PCDcachecache.db”cache”