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Encountered an improper argument. When saving any symbol file.

		
	
				

			

									
					    eewiz
					
							

            
            			
				
									
											
			
			
				
			
			
			    	
			                    
                
				                on May 10, 2026 
				
			
			
		

		
		                    	    

        	    
Thread Summary

                The user encounters an 'improper argument' error when saving symbol files (.asy) in LTspice on Windows 10. The error persists despite the save operation working, and is tied to a specific .asc file in a long-running LTspice instance. A second, recently opened LTspice instance does not exhibit the error. The user suggests using Procmon to investigate the Windows return codes causing the issue.
                        	    

                
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Category: Software

    		        		            		    
Product Number:  LTspice 

    		        		        		        
Software Version: 26.0.1

    		    		    

		    		    
		    			

			    
Hello All:
 
Any time I save a symbol I get this:
 
 I have received this message in the past.
 It was eliminated then by rebooting my win10 box.
 It has now returned and I would like to determine the cause.
 
 Review, after a save produces the error message, shows that save works.
 Opening the symbol again and saving, without changing the file, also produces the error message.
 
I figure that ADI is the only entity that knows why LTspice would throw this error when saving any symbol file.
 If one would like me to perform a test or submit data, I would be happy to do so.
 
 All for now.

			

			
									
		                             
                        

    

                                            
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                on May 10, 2026 6:43 PM
            
            
						
			            		
    
		
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    Note - I am in the LTspice usergroup where this was reported.  There have been a small number of cases of this error mentioned in that group, all since 2019, and all involving Windows 10 systems.
    

    I don't really know, but my spidey sense is that Windows might be sending a funny completion code or error code to LTspice after successfully saving the file, which then displays it on the screen.  (In other words, maybe the error did not come from LTspice.)
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
						
				
				
		
		
    
			
		
    
	
    

    

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                on May 10, 2026 9:21 PM
            
            
												
						in reply to AndyI
					
										
			            		
    
		
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    Hello All:
     
    

    I posted this recently in the LTspice usergroup.

    Very interesting.
     I start a 2nd copy of 26.0.1 from a desktop shortcut.
     I drop the trouble making file onto it that is already open in the 1st copy of 26.0.1.
     The original troubled save from the 1st copy of 26.0.1 did save the changes despite the error message.
     Now I have two copies of the same .asc file open in two copies of 26.0.1.
     
     The 2nd copy of 26.0.1 has no issue.
     The 2nd copy of 26.0.1 saves all .asy files without the error message.
     
     The 1st copy of 26.0.1 still produces the error.
     The 2nd copy of 26.0.1 does not produce the error.
     
     The 1st copy of 26.0.1 that produces the error, has been open for more than a week.
     The 2nd copy of 26.0.1 has been open for less than an hour.
     
     I posted about this issue on engineer zone.
     It would be lovely if they replied with the windows return code or codes that trigger that message.
     
     At this point I am not so sure it actually requires a reboot.
     Possibly closing and reopening the troubled 26.0.1 would eliminate the issue, but I don't want to go there yet.
     
     If I open a different .asc file B in both the 1st and 2nd copies of 26.0.1, there is no issue in either copy when saving any .asy file from that different .asc file B.
     
     The 1st copy of 26.0.1 still produces the .asy save error on .asc file A and no error on .asc file B.
     The second copy of 26.0.1 produces no .asy file save error for both .asc file A and .asc file B.
    

    

     
    

    The issue is somehow tied to the representation of .asc file A as stored in the memory of the 1st copy of 26.0.1.
     Opening that same .asc file A in a 2nd copy of 26.0.1 has no issue in the shortrun.
    

     
    

    All for now
    

    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
						
				
				
		
		
    
			
		
    
	
    

    

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    •  Analog Employees  
    
            
						
                            
            
            				
            
                on May 11, 2026 12:36 PM
            
            
												
						in reply to eewiz
					
										
			            		
    
		
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    Hi  ,  ,
    

    Hmmm. I've gotten this error using a ported version of LTspice on my Mac. I had thought it was specific to the port combined with directory permissions. 
    

    Side note: M$ has surreptitiously changed some Windows write permissions without clearly documenting the change. I'm seeing notes about this in IT circles. We also encountered a problem with certain installs of Win 11 and how it was handling the .ini. But, you are seeing this in Win 10…so.
    

    I'll try to reproduce your results and look into it more.
    

    mike
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
						
				
						
				
				
		
		
    
			
		
    
	
    

    

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                on May 16, 2026 11:48 AM
            
            
												
						in reply to MStokowski
					
										
			            		
    
		
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    Thank you Mike for the addition of this matter to what must be a long list of to do's.
    I have only seen this issue three times in the past.
    When I see it again, I will expend the effort to use Procmon to find what win10 is doing to cause this.

    Thank You again.

    eewiz
    
			
    

		
			
	      

		
		
	
    
	
    
		
    
			
		
    
	
    
	
    
		
						
				
						
						
				
				
		
		
    
			
		
    
	
    

    

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