During installation the DATA path directory (where the logs reside) can be changed if required.
There is an easy way to locate the path to the DATA folder using the following steps:
1. Use Windows Explorer
2. Locate the installation path where you installed Transform (example below)
C:\Program Files (x86)\Bottomline Technologies\Transform Foundation Server\config\system-config.xml
3. Open system-config.xml
There will be a line in the XML: (example below)
<stringVariable name=""DATAPATH"">D:\Data</stringVariable>
4. Under the DATA folder you will find the Logs folder