I had a problem with one of my converted 5.5 files that may be the same issue. What fields are used as key fields in the relationship? Is one of them a calculation field? If so, check that calculation field's definition. During conversion, filemaker adds the function "getasnumber()" in numerous places throughout your field definitions and other expressions. 99.9% of the time, this is harmless, but I had one key field that wouldn't evaluate correctly (and this broke the relationship) until I removed this function.
You can also try re-indexing the fields. Open Manage | Database and select fields. Find the field in question and double-click it to bring up it's field options. Click the storage tab, turn off indexing and click OK to close the options dialog. Now double-click the field again and repeat these steps to turn it back on.
To see what fields are used in the relationship in fmp 10, open Manage | Database and click the relationships tab. Your simple fmp 5 table has now been converted into this Entity-Relationship style chart of your relationships. If you can't figure it out, the help file has some good entries that identify the function of each button etc. To see the relationship details, double click a relationship line and you'll get a dialog with much of the same details shown as was found in your FMP 5 relationships dialog box.
I actually figured it out. I appreciate your help but my problem was in the relationship manager. I went to MANAGE under FILE with the specific field highlighted and checkout the EXTERNAL DATA SOURCES. It turns out that the path names were wrong. I corrected them and everything works so far perfectly. I had some one layout these databases for me 13 years ago o I am NOT familiar with any of it. Thanx
I suggest opening Manage | External Datasources if you haven't already done so. If your files are like mine were, you'll find quite a bit of duplicate references and references that include paths to now defunct locations. By using the Database Design Report in FMP advanced, you can trace down each reference and merge duplicate/delete obsolete references.
Thank you. I plan to make some reports and such, so it's good to know I can find help if needed.