Installscript project - changing productName effects error 1706

[h_violet]

(Installshield 2014)

Installscript-project with merge-module holder object which contains several objects/merge-modules. 
Project served well for years, where we regularly shipped revision updates.

Last week we changed the ProductName from say "Name V1" to "Name V2" and the ProductVersion from say 1.0 to 2.0.
From this time up we get error 1706 - "no valid source found" each time we install an update .
The error occurs exactly when the merge-module holder is installed.

The error also occurs if we update a first-time installation of a version with already changed productName.

What has ProductName to do with merge-Module sources?

Any help would be greatly appreciated.
Thanks and Best Regards H.

[varul]

Your project type is Pure installscript or installscript MSI?

If you dont change the product name is it working fine,  If you are changing the product name then try to create a major upgrade upgrade 

Please refer the Kb link for error 1706,

https://community.flexera.com/t5/InstallShield-Knowledge-Base/Windows-Installer-Error-1706/ta-p/4707

[h_violet]

Hi varul, thanks for your reply,

we are using pure installscript. So, as to my knoledge, for this project type there is nothing like a "Major Upgrade".

I have tried some of the resolutions described in the above mentioned link:
Creating a new Release with a different name.
Caching the merge-modules.

Unfortunately, this did not fix the error.

Regards, Heiner.

[MarkusLatz]

In order to be able to possibly understand this, which merge modules do you have in this merge module holder object ?

regards

Markus