Corner map/Overlay Map not saving when I reenter a saved instance

Recently, I have been having trouble with the Corner and Overlay map feature. Normally, when a part of a map is discovered, it shows up on the corner map, and saves to the instance, so that if a player leaves the instance (for trade, dying, etc.), they will be able to see the map of the instance upon reentry. But, for me the mini-map does not save. When I die, or leave the instance, when I return to the instance, the map itself is the same, and the mob drops are still there, but the corner map and overlay map are not saved.

As you can imagine, this can lead to some pretty irritating quests. If I die, I am forced to discover the map all over again, instead of being able to quickly run through the already discovered area.

This feature started right after I graduated into merciless difficulty, but I doubt that the difficulty change was the reason. I had recently deleted some of the Path of Exile files on the computer to minimize the file size (which had no effect on gameplay), and changed some of the folder names on the C: drive to hide it from my roommate. But, for some reason, the game began to freeze and stall very often, so I deleted the game and tried a fresh install. But I logged on today, and not only would the minimap not save, but neither would the graphical settings. If I close the game, I have to optimize the graphical settings upon relogging, which is a long and difficult process due to my slow computer.

I had another user tell me it was happening to him too, but he didn't seem too concerned. If there's something you can suggest to prevent this from happening further, I would be all ears.

Thanks

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