If you’re still using Visual SourceSafe (1), but you’d like to upgrade the tools used for visual diffing and merging, here’s how to plug in DiffMerge:

In VSS 2005’s Tools | Options dialog, you’ll want to first Add an entry for Operation File Difference. For the File Extension, enter .*

For the command line, you’ll need to find the full location of DiffMerge.exe. By default, it’s in c:\program files\sourcegear\diffmerge; if your system is different, substitute accordingly. Assuming the default path, your command line would be (all one line):

C:\Program Files\SourceGear\DiffMerge\diffmerge.exe --title1="original version" --title2="modified version" %1 %2

Similarly, to set DiffMerge as your Visual Merge too, add a File Merge entry, whose command line is:

C:\Program Files\SourceGear\DiffMerge\diffmerge.exe --title1="source branch" --title2="base version" --title3="destination branch" --result=%4 %1 %3 %2

When all’s said and done, your options dialog will look something like:

And Visual Merging will lead you to:

  1. Why? Please stop that. If not Vault, then something else)