Sol Web Solutions Blog
Sol Web Solutions Blog is aimed to help, inform, educate and enable our site visitors.
The server could not complete your request when trying to copy and modify Collect Signatures Workflow
You may get an error of "The server could not complete your request" when trying to copy and modify a Collect Signatures Workflow in SharePoint 2010.
Instead of doing this from a sub-site, go to the root site and try the same thing in SharePoint designer.
That fixed my issue.