In Enterprise Guide 4.3, I kept running into this problem. Whenever I had a remote server, and a library created on it, I couldn't create a new table in the library without first creating a stub table metadata object. I couldn't take a Query Builder's output going to WORK, and instead change that to a permanent library and expect it to work. EG would send the right code to SAS, and SAS would return this error:
ERROR: You cannot create or delete datasets, views or indexes in this mode. Try the option METAOUT=DATA. Use Proc Metalib to create metadata for datasets.
The problem is that by default, Enterprise Guide opens libraries from the server in a sort of read-only mode. It's not allowed to create (or delete) datasets that were not already defined and registered in the metadata server. This protects us from cluttering up the server and keeps the DBAs from yelling at us, but might not be expected, especially in a single-user environment.
From SAS's perspective, we had allocated a library using the Metadata LIBNAME Engine, and tried to create a table in the library that wasn't registered. It sends back a totally reasonable error message, but to us using Enterprise Guide it's totally cryptic. Totally. We, as the user, probably just said "hey, use this library", and are probably unaware of what libname engine was used (and maybe even unaware of what a libname engine even is).
There's an easy way to fix this, and it can be done from Enterprise Guide. It's easy to miss though, because it must be done to a library while it is unassigned. If the library is assigned (the icon is yellow and colorful), unassign it (so the icon is grey and not filled in). You may have to close your current project because some of your tables from it might still be in use.
Find the library in the library under your server ("SASApp" by default). Right click on it and open the properties. If the library is still assigned, you'll get a read-only modal window come up, but if the library was unassigned, you'll be able to change stuff.
Click the second option on the left, "Assignment" and then uncheck the option "Show only tables with metadata definitions".