what if guys there's a missing DLL file in your

system. What will you do?

for example I had a experience in DLL problem, when I try to install something an error pop ups cannot find SHELL.DLL, right after this I tried to find a shell.dll file in the internet to install in my pc but I cant find anything and I decided to copy from another Pc from a network it doesn't work at all.

Im really busy in my business in this computer cafe due to overloading customers , so I decided to reformat the PC.

my question here is what if this will happen again is there a site which i can downlaod most needed DLL files or like what I did, is it advisable to copy a DLL file in a network or in another pc? any suggwestions guys any post regarding this DLL files.