viewer.html with file pdf with character '+' doesn't work ....

[lenoil]

Hi,
if I enter a following url it works : web/viewer.html?file=XXX YYY ZZ.pdf
but
if I enter a following url it doesn't work : web/viewer.html?file=XXX YYY+ZZ.pdf

I try to encode pdf file name but it don't resolve
The character + seems to be a problem with the version older browsers but it works with modern browser

Do you have a solution ?

Thanks you very much