Programs claim they are already running on startup.

A week or so back I was having trouble getting LibreOffice to start. When I would try to start it, it would reply that another instance was already running and refuse to start. Solution finally turned out to be to delete an ini file with an astoundingly long name from the Data folder. Today I was trying to start up Irfanview portable and encountered the same problem with the same solution. I've used portable apps for years and never encountered this before. Has some general change occurred which causes this? Do we need a cleanup app? Or have I just been unlucky?

-----Paul-----