Below are some of the errors in a support project which will be a great help for new learners:

by: Anoo

1) RFC connection lost.
A) We can check out in the SM59 t-code
RFC Destination
+ R/3 connection
CRD client (our r/3 client)
double click..test connection in menu

2) Invalid characters while loading.
A) Change them in the PSA & load them.

3) ALEREMOTE user is locked.
1) Ask your Basis team to release the user. It is mostly ALEREMOTE.
2) Password Changed
3) Number of incorrect attempts to login into ALEREMOTE.
4) USE SM12 t-code to find out are there any locks.

4) Lower case letters not allowed.
A) Uncheck the lower case letters check box under "general" tab in the info object.

5) While loading the data I am getting messeage that 'Record the field mentioned in the errror message is not mapped to any infoboject in the transfer rule'.
A)

6) Object locked.
A) It might be locked by some other process or a user. Also check for authorizations

7) "Non-updated Idocs found in Source System".
A) Check whether any TRFC s strucked in source system. You can check it in SM58.  If no TRFC s are there then better trigger the load again i.e., change the status to red, delete the bad request and run the load.   Check whether the load is Delta or Full.  If it is full just go ahead with the above step.

If it is Delta check wheteher it is source system or BW. If it is source system go for repeat delta. If it is BW then you need to reset Data Mart status.

8) While loading master data, one of the datapackage has a red light error message: Master data/text of characteristic ZCUSTSAL already deleted.
A)

9) Extraction job aborted in r3
A) It might have got cancelled due to running for more than the expected time, or may be cancelled by R/3 users if it is hampering the performance.

10) Request couldn't be activated because there is another request in the psa with a smaller sid
A) 

11) Repeat of last delta not possible.
A) Repeat of last delta is not a option, but a mandate, in case the delta run failed.  In such a case, we cant run the simple delta again.  The system is going to run a repeat of last delta, so as to collect the failed delta's data again as well as any data collect till now right from failure.

For repeat of last delta to be run, we should have the previous delta failed.  Lets assume, in your case, I am not sure, if the delta got falied or deleted. If this is a deletion, then we need to catch hold of the request and make the status to red. This is going to tell the system that the delta failed(although it ran successfully, but you are forcing this message to the system).  Now, if you run the delta info package, it will fetch the data related to 22nd plus all the changes from there on till today.

An essential point here, you should not have run any deltas after 22nd till now. Then only repeat of last delta is going to work. Otherwise only option is to run a repair full request with data selections, if we know selection parameters.

12) Datasource not replicated
A) Replicate the datasource from R/3 through source system in the AWB & assign it to the infosource and activate it again.

13) Datasource/transfer structure not active.
A) Use the function module RS_TRANSTRU_ACTIVATE_ALL to activate it

14) ODS activation error.
A) ODS activation errors can occur mainly due to following reasons-
1.Invalid characters (# like characters)
2.Invalid data values for units/currencies etc
3.Invalid values for data types of char & key figures.
4.Error in generating SID values for some data.

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• What Is Different Between ODS & IC
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• Tickets and Authorization in SAP Business Warehouse

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