Print this page

Compile Error: Method does not exist or incorrect signature: System.Test.testInstall (MyPostInstallClass, NULL)

Knowledge Article Number 000182136
Description The cause for this compiler error is a user defined interface called "InstallHandler".

Generally, InstallHandler class don't have the system namespace so it causes namespace conflicts when we have own classes/interfaces with the same name.(i.e : InstallHandler ) So our custom InstallHandler don't know what is 'testInstall'

Compiler will throw this error message as it does not recognize the standard methods:

Error: Compile Error: Method does not exist or incorrect signature: System.Test.testInstall(MyPostInstallClass, NULL)









 
Resolution To fix this issue you need to edit the PostInstallClass to implement system.InstallHandler, i.e: 

global class PostInstallClass implements system.InstallHandler { 
global void onInstall(InstallContext context) {} 


Related Dev Doc: InstallHandler Interface​

 





promote demote