Tutorial:Accessing sequences using batch entrez

Question

[mawia.martha]

Hello,

What format should your local file be when trying to achieve sequences from batch entrez? I used an .xml format and it says

The following records can't be retrieved:
Id=PK: nuccore: Wrong UID PK
An illegal character in a token. Possible wrong file format. Request processing canceled.

Please assist

Martha

[Sej Modha]

Could you please provide a sample command that would generate this error? PS: I think this post should be categorized as a question and not a tutorial, please update.