Using blend files with a group of people running differents systems can lead to problems with files not loading correctly on other systems.
Blender now has some tools for managing invalid path errors for the following path types.
This will make all paths relative to the current blend file, after this you'll need to resave your blend file.
Its important to use relative paths when collaborating with others.
This makes all paths absolute, and can be used before moving a blend file to a new location, which would break normally make all relative paths. after moving the blend file, you can load an make relative again.
This is a useful function to run before sending work to a renderfarm or uploading to a client to make sure all your paths are valid. If there are any invalid paths they are written to a text block.
This searches for filenames that have invalid paths.
The prompts you to select a directory where your files are and files with corresponding names will be will be used.
To ensure thumbnail images are not used the largest file is selected when there is more then one match.
This option simply tells blender whether to set paths to relative by default when linking or loading in new files. it can be accessed from the user preferences, file paths section.