After the service pack update 2 for ACADE 2013 ( don't know if the update had anything to do with it) I was having trouble inserting symbols from the icon menu on some drawings I was trying to update. Some symbols like relay contacts, etc worked fine yet others when I tried to insert them like Temp switch, limit switch, etc I would get the "AutoCAD Message" pop up saying "File Not Found: HTS.dwg" or whatever number of the symbol I was trying to insert. It then lists all the paths it checked below it.
What is strange is on the next sheet in the set of drawings I might be able to insert that same symbol but not another one I was able to on the previous drawing will not.
I removed the Service pack but the problem remains.
I tried doing it in a new drawing I created to test and it happens and in some old project drawings too.
The drawings I was trying to update were ACADE 2010 originally so I opened a copy of the originals with ACADE 2010 and the same thing is happening.
Thanks for your help.
Try this:
In the Project Manager, Right-click on your project and select Properties. In the Project Settings Tab expand and examine the Library and Icon Menu Paths. Press the Default button and see if this helps.
If you are using a different ACADE version the file paths may need to be updated. Note: These file paths are stored in the project file *.WDP.