I love these games but a can’t play them on steam 
I changed the resolution on opposing force one time and ever since all the buttons have disappeared for all three games.
I can load up the background image and get the roll over button sounds effect but i can’t do anything else.
Any helpers?
and thank in advance, unless this problem remains unsolved.:retard:
Try right-clicking one of them in the Steam Games list, going to ‘Set Launch Options’ and type in your monitor’s native resolution: -w xxxx -h xxxx - e.g: -w 1280 -h 1024 - then start it and see if it’s fixed. 
Just a suggestion. 
Nope
Now it’s just bigger with no buttons.
Problem solved: In Steam, right click on HL and select Properties, then Set Launch Options.
Try -w800 -gl (make sure you use a space between them). Instead of -gl, you can also try -d3d or -soft.
If that doesn’t work, try the -safe option mentioned in this Support article.
(The -dxlevel options won’t work for HL1. -autoconfig may.)
—Another thing you can try is changing your Download Region in Steam, then verify the game cache again.
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