Occasionally during an update of Traveller from version 6826 the system will return and warn the user that there is not enough disk space when there is clearly ample space. The instructions below outline the workaround to this situation whilst it still exists.
When the error message appears identifying the deficiency it would be extremely helpful to be able to have a screen print of the error. (Shown below)

Site has new 6826 CD
Site has OLD 6826 CD
1) Create a c:\%Windows Folder%\DevBox.ini with the following lines :
[Development]
DevBox=True
[Support]
IgnoreDriveSpace=True

2) Re launch the installation, the following screen (or similar) will appear.

3) Please note that as soon as this screen is displayed the devbox.ini file is altered, the IgnoreDriveSpace line is REMOVED. It must be replaced to launch the install again. This is to prevent further installs ignoring the check because we never set it back.
1) If the site has the old 6826 CD then an obvious solution is to send the new one, however - if that is not desirable then the following instructions can be used.
2) Copy the entire contents of the CD into a folder somewhere on the system in question.
3) Download the updated setupsvr here.
4) Extract the SetupSVR.exe and replace the one that is found on the root of the CD, you will have to replace the copy of the CD as you cannot write directly to it.
5) Create a shortcut from SetupSVR.exe to the desktop so that the user can be instructed to run this shortcut instead of using the CD.
6) Follow the steps outlined in the "Site has new 6826 CD" the only difference will be that point 2 where you re launch the installation, you MUST use the shortcut on the desktop, not the CD.