If the D25LT software appears to have "frozen" (particularly when beginning the long-term drift test), you may actually have a printer problem. Suggestions for correcting the problem may be found here.
In other cases, the system may seem to freeze for a number of seconds after choosing a product setup job for use or when saving measurements. This happens when many measurements (generally 300 or more) are stored in the job. It takes time for the processor to recall all the measurements on opening the job or to save all the measurements on saving new measurements. System speed will increase if you begin saving measurements in a new product setup job or if you delete all unneeded measurements. For instruments containing system software version 1.70.7334 or higher (visible at the bottom of the Diagnostics menu screen), choosing CSV as the data file format on the Preferences screen may also help speed operation.
If additional assistance is required, you may contact HunterLab.