WHMCS Module not working

[theo]

Hey,


I just setup a new server with Vesta and WHMCS, but when I test the module, I get this error:

Module Create Failed - Service ID: 2 - Error: Error: user exists

error.log:
2017-01-13 12:41:08 v-add-user '' '******' '[redacted]' 'default' '[redacted]' '[redacted]' [Error 4]

I have no clue what is doing on, as this user doesn't exist in Vesta at all.

Help?

[vikhyat]

Install WHMCS 5.x first and successfully install the module in it and then upgrade WHMCS to a later version. This worked for me.