Error 1303. The installer has insufficient privileges to access this directory (4338888)

User had "Full Control" over the installed directory and was able to manually add and delete files/folders, but LiteSpeed installer still errorred with "Error 1303. The installer has insufficient privileges to access this directory".

1. Create a temporary folder called "LiteSpeed" on the local server's drive
2. Give everyone "Full Control" on the folder
3. Share the LiteSpeed folder to everyone

4. If steps 1 through 3 still failed, rerun Instance Configuration, select IGNORE for all instances at the SQL Instance setup screen.