I had a related issue -- I wanted to create import specs from existing Excel record layouts, without having to retype names, displacements etc.
Let's say you want to create a spec for a file "newdata", for which you have a spreadsheet with names, start pos and lengths.
Process:
1. Read the Microsoft bulletin prev mentioned.
2. Open the MSysIMEXSpecs table, and create a new rec, by copying an existing rec. Note the SpecID # has bumped up, and change the SpecName to "newdata". Exit (save)
3. Open MSysIMEXColumns, and copy the headings and a few records from an existing spec - pref close to what you want.Paste these rows into a new Excel sheet.
4. Copy the field names from the spreadsheet of "newdata" into the FieldName column. Copy the start positions into the Start col. and the field sizes into the Width col.
5. Copy the data in the other cols into all rows now populated by the "newdata" fieldnames, but use the new SpecID #.
6. Check what you have makes sense -- lengths, etc. and NO duplicate fieldnames.
7. As a precaution, select only those cells you have used, and create a new book by pasting. Save this.
8. Go back to Access and "get external data" / "import" / the spreadsheet you just created, First row with headings, into "existing table" MSysIMEXColumns .
Now when you need to import data that matches the "newdata" spec, just select it from the "advanced" / "specs".