I also have problems with mthelp on Windows XP. Today I've tested again and works with some files but fail with others.
From a cmd window typing mthelp a0 (or memman, pgfplotstable, tabularx) open corresponding manual in pdf default viewer or yap. It doesn't open the browser and shows a page with links to all related files.
It seems that this is a Windows XP problem. It works under Windows 7.
I also have problems with mthelp on Windows XP. Today I've tested again and works with some files but fail with others.
From a cmd window typing mthelp a0 (or memman, pgfplotstable, tabularx) open corresponding manual in pdf default viewer or yap. It doesn't open the browser and shows a page with links to all related files.
mthelp anysize (or acronym, animate, tabu, beamer, pgfplots) fails
I could not find any similarities neither between succesful packages nor unsuccseful ones.
Best regards,
Ignasi Furió