@MerveS  I'm not sure what you're asking here.  I'm assuming you are enquiring about either the Pega Trial/ Community Edition or the Pega Personal Edition software.

You should be able to access these via your My Pega -> My Software pages.

If you are asking why these (and Enterprise Edition software) are only available in the latest Pega version, please see our response here. 

The FAQ page informs you:

 If you think you require an older version of Pega Platform or other Pega software, enter a support request with Pega Support. In the INCIDENT please provide the contract number and the list of products/versions you are looking to download.

Hi @MerveS

I think we don't have 8.7.3 personal Edition Software we have 8.7 only, if you Download software from My Software ( https://my.pega.com/mypegaprd/PRAuth/SSO/MyPega/MySoftware ) through your PDN Account, it will only download the 8.7 Version.

If you want 8.8 Version We have wait for few more weeks

Here you can find the Previous post about 8.8 Version.

https://support.pega.com/question/when-will-pega-platform-88-be-released

I hope this will hep you,

Thanks,

Ashok