If I use findItemsAdvanced with my affiliate info, all is well and I get what appears to be correct urls back (
rover.ebay.com...), however with findCompletedItems I get the following error. errorId "1", domain "Marketplace", severity "Error", category "System", message "Internal application error", subdomain "Search". If I take out the affiliate info however, the call works fine. Is this a bug? If not, how would I go about building affiliate links myself from the returned urls? I'm using the C# SDK if this makes any difference. Thanks,
Sounds like a bug. There have been several quirks and bugs with the fCI call (or its docs page) over the years. Sometimes we report them, sometimes we don't. Sometimes eBay fixes 'em, sometimes not. As clickimusprime is implying, you can/should build your own affiliate/rover links. It's not complicated. You just need to carefully follow a syntax/template when building your URLs.