I purchased Nuvi 2797LMT three days ago and I saw there was a new update so I went ahead and start. When it start out with 13 hours left, I wasn't surprised since the map is huge, so I let it update the whole night and is still 13 hours remaining.. I went ahead and restart the update, the hours remaining changes frequently and I thought it must be progressing and I left it for another whole night. The bar progress like 10% I left it alone for another 15 hours= no change. And today, we are still trying to update the map. We have left it alone for like three full night, why it is sooo slow?
I am sorry for the troubles. Please see the FAQ article: What should I do if I am having problems downloading updates in Garmin Express? for some suggestions, system requirements etc. If all system requirements are met I suggest you disconnect the Nuvi, restart the computer then start the update again. If you continue to have troubles please contact Garmin Product support by phone.