You need at least 2 GB of free RAM (including virtual RAM) for the installer to run.
After unpacking, the game occupies up to 61 GB on your drive. Gameplay Experience (XL Edition)
The is a highly compressed version of the action-adventure sandbox game, reducing the original ~60 GB file size to approximately 16.7 GB . This edition includes the base game (v1.05) and all released DLCs, such as the Air, Land and Sea Pass . Repack Performance & Technical Details
Users encountering installation errors like ISDone.dll often solve them by disabling antivirus software, increasing virtual RAM to 8GB, or using the "2GB RAM limit" option in the installer. Critical Reception