I installed the sf extension for vscode and got everything to run with the default package.xml. I exported the whole package from my org with the help of Package builder and inserted it to the package.xml in the manifest folder. Now retrieve source from org exits with this error:
> Starting SFDX: Retrieve Source from Org
>
> 15:10:34.965 sfdx force:source:retrieve --manifest
> p:\sf_code\developer\manifest\package.xml ERROR running
> force:source:retrieve: EISDIR: illegal operation on a directory, read
> 15:12:45.841 sfdx force:source:retrieve --manifest
> p:\sf_code\developer\manifest\package.xml ended with exit code 1
I get the same error when entering the command to the sfcli outside vscode
-u MyConnectedOrg
parameter in theforce:source:retrieve
command