I have 14000+ lines of a database, that I want to edit with Notepad++. All these lines should start with 1000 and I therefore want to delete CR LF at the end of those lines that are not followed by 1000. Eg. 1000 16 04000 CRLF sdfsdf 15 sdf de 05550 CRLF 1000 16 04000 CRLF 1000 16 04000 CRLF 5. sdkfd dksds 16 0555 CRLF 10/10/14 sdfsdf CRLF should after find and replace look like 1000 16 04000 sdfsdf 15 sdf de 05550 CRLF 1000 16 04000 CRLF 1000 16 04000 5. sdkfd dksds 16 0555 10 sdfsdf CRLF I have tried with find what: \r\n([^1000]) Replace with _\1 However, this doesn't seem to remove lines starting with a number (like 5. or 10/10/14). Is it possible to make just one RegEx to find and remove all line breaks that isn't followed by 1000? "_" indicating a "space"