Do you use special (="non-ASCII") characters in the TER or HGT file's name?
If so, try to rename. You would then need to choose the "replace function" for old scenarios relying on these maps as these scenarios would still reference the old file names, but otherwise it should work............NO can not do this lost map when I installed 4.1 I bought STEEL BEASTS in 2000 and all versions sense have never had trouble like this before I am now reinstalling fore the fourth time. Bought 53 dollar package so I wouldn't have too spend time downloading thou I have fast internet. LOVE LOVE this sim best software I have ever owned. Tankyou