Object Cache Redirects to Other site on same server

Hello.

Sorry if the answer is somewhere else, but this seems like an odd config issue that I am stumped on. I’m using this plugin on several sites, and it works just fine (as expected). However, on two sites I’ve attempted to enable this plugin, and it redirects me to another site entirely, on the same server. If I delete the object-cache.php file from wp-content, then I can get back to the original site. I know this is a bit vague, but is there something you think I could look for in an effort to figure out why this is happening?

Thanks so much.
Howard