I believe I've figured out the problem, and I cannot believe it didn't occur to me immediately. If you put your packages in a directory named something other than "packages" (or rename your existing "packages" directory), does the install complete successfully?
I believe I've figured out the problem, and I cannot believe it didn't occur to me immediately. If you put your packages in a directory named something other than "packages" (or rename your existing "packages" directory), does the install complete successfully?