Sorry for taking so long in replying but I have been working on the issue.
My media files are all within the Project.
Family Historian Projects>name tree>name Tree.fh_data>Media
I have trawled through this folder and there are no files (all 6,458) showing the blank envelope.
In the Media List there are 46 media files with this issue.
I have also checked and there are no unlinked media files.
Tried closing FH and re-opening but made no difference. Can open Tools but cannot access external file links
Tried re-booting computer but made no difference cannot access external file links
I clicked on one of the problem files in Media list and get the “Parameter incorrect”. It will let me expand using the plus icon on the left and filenames are exactly the same as the one in both the media list and the Family Historian Projects>name tree>name Tree.fh_data>Media folder.
If I go to the Focus Folder and the Media tab of the individual the “Parameter Incorrect” file is relevant to and click on it, as it has the same filename, I can see it displayed in the window below. Go to that filename in the Media list and it is shown as the envelope type icon and clicking on it gives the Parameter incorrect message.
I have now managed to fix all of the 46 media files showing the Parameter message.
I tried various options which I can detail for you if you think it would be useful to others or in finding what has caused this issue, however what has worked for me follows.
I made a copy of the problem file from the Family Historian Projects>name tree>name Tree.fh_data>Media folder and saved it in a separate folder out with FH. I used the Downloads folder.
Most of the problem files I had are in TIFF format. I then deleted the problem file from the Family Historian Projects>name tree>name Tree.fh_data>Media folder and the Media list. So deleted from FH entirely.
I then opened the saved file in a photo editing software and saved it as a JPEG instead of TIFF with the same filename. I now had a JPEG and a TIFF file in the Download folder.
With the appropriate record that the file belonged to open in the Media tab I dragged the JPEG version on to the FH icon in the taskbar and added to the record. This creates a new media number file and it displays correctly.
I then deleted the JPEG and TIFF files from the Download folder.
There were 5 or 6 JPEG files out of the 46 giving the Parameter message and as they were already JPEG format I did not go through the photo editing part but instead dragged them on to the FH icon and added them to the relevant record. This did not work.
When I checked, despite it being a new file added to the Media list, it was still showing the envelope icon and giving the Parameter message. I then repeated the process but included the photo editing part. In effect saving a JPEG file as a JPEG file with the same name. When dragged on to the FH icon and added to the relevant record it displayed perfectly and no longer showed the Parameter message.
A word of caution. If the problem file is one with links to several individuals such as a census record, all the links need to be re-established as the original has been deleted so have all the links.
I would stress that I am not very technically minded and there may well be a much easier way to resolve the problem. I was simply trying out various options and those described are what worked for me.
I do not know if the External Links would help as a) I cannot access it and b) I have never used it.
You mentioned a Plugin you created. Would it pick up these files showing the Parameter Incorrect error?